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Reggie Whiddon
Reggie Whiddon,
Category: Dodge
Satisfied Customers: 162
Experience:  Lead tech at river regions auto
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I have a 2002 Dodge Ram 1500 w/ 4.7L my daughter was driving

Customer Question

Hi Brad I have a 2002 Dodge Ram 1500 w/ 4.7L my daughter was driving and truck stalled on the hwy we towed to the house and checked it and it had I code showing P1391 for the cam/crank sensor or timing off so we changed the cam position sensor first nothing just cranks no start kinda rough cranking , then changed crank postion sensor again nothing cranks no start, then we pulled valve covers and timing cover off to check and see if jumped time and sure enough when the timing marks on primary chain were lined up the cam marks were never lined up so we replaced timing chain and tensiors and guides so put back together expecting it to just crank up and got in and cranks smoother but still no start so we checked fuel pressure and had fuel pressure, but we had no fire then we put noid light on injector harness and no light so we looked online and found the just answer post that you answered for 2002 Dodge ram 1500 4x4 crank, no start problem so we started using it to check things and on relay 57 engine control relay/asd I checked pins 30 and 85 and only one had 12v the other nothing so I removed the integrated power module or just got to where I could check wires and I checked the dark green/orange wire and it had nothing so I went over to the pcm and checked over there and it had nothing no 12v so theres where I'm at
Submitted: 1 year ago.
Category: Dodge
Expert:  Reggie Whiddon replied 1 year ago.

Hello 30 and 85 should both be hot at all times, and they both get there voltage from the same place Fuse #2 30 amp which is located inside the intergrated power module. If you have power only on one of them your going to have a problem insdie the power module. .And power only on one of those terminals will cause a no start, If you cant find the short, try running a jumper from one to the other and see what happens.

Customer: replied 1 year ago.
Hi Reggie sorry taking so long to get back with you I've been out of town and its been raining almost every night when I get home so I haven't tried to jump yet but the dark green/orange wire feeding the fuse and/or relay has no voltage and so I tested over at pcm and no voltage coming out of pcm there should be voltage on that wire and that's where it starts according to the wiring diagram is that correct?
Expert:  Reggie Whiddon replied 1 year ago.

No sir 85 and 30 both get there power from same source fuse 2 is 30 a and supplies both 30 and 85

Expert:  Reggie Whiddon replied 1 year ago.

I believe you have found your problem it will be internal to thr ipdm (fusebox) I would run a jumper between the 2 and if truck cranks I'd make it permanent, they get a lot for those ipdm.

Please let me know

Customer: replied 1 year ago.
ok so finally got back into to town long enough to jumper the wires and I now have voltage at both pins 30 and 85 but still no start.
Expert:  Reggie Whiddon replied 1 year ago.

You would put the jumper between 87 and 30 that would complete the ckt to starter solenoid

Customer: replied 1 year ago.
ok so I'll be heading home in a few and I'll try to jumper 30 and 87 but just so we r not confused the truck is cranking just not starting it cranks over fine just no spark or pulse to injectors as per original post.
Customer: replied 1 year ago.
Ok so 87 has no contact points in it's empty now 87a does have contact points
Customer: replied 1 year ago.
Ok so had that backwards but jumpered and still no start
Expert:  Reggie Whiddon replied 1 year ago.

If you jumped 30 to 87 and it would not start or turn over, check the power supply it should be on 30 If you have 12 volts on 30 and you jumped it to 87 it should have made the starter turn over if it didnt you either have a bad starter, or an open in the wire to it. I apologize I could not get on here much today, i will be on more tomorrow, lets get this thing going.

Customer: replied 1 year ago.
It has always turned over just not fired up and ran but yes it's turning over fine just not starting and I jumped 30 and 87
Customer: replied 1 year ago.
It has always turned over just not fired up and ran but yes it's turning over fine just not starting and I jumped 30 and 87
Customer: replied 1 year ago.
Have you found anything else yet
Expert:  Reggie Whiddon replied 1 year ago.

Yes sir I am sorry hadnt heard fom you in a while it looked like the question had closed. I apologize again i understood you wrong in that I thought the truck would not turn over. So lets start from the beginning, you turn the key it spins over but want start. Now you are speaking of the asd relay, which is the computer relay, and you have power on 30 and jumped that power to 87 and it still did not start, Do you have data on your scan tool? If so what is the cam crank correlation look like, If you have fire, and fuel pressure and are pulsing the injectors, we have got to verify timing

Customer: replied 1 year ago.
The injectors r not pulsing as per noid light and as far as fire I have no spark coming from coils the timing we replaced the timing chain and made sure all marks on primary and secondary chains lined up
Expert:  Reggie Whiddon replied 1 year ago.

Okay do you have a scanner or code reader? We need to see if the pcm is getting a cam and crank signal.

Customer: replied 1 year ago.
Ok so I had just a few min before had to leave for work and I hook up my scanner and did live feed and showed no rpms or nothing is that where to look for cam or crank signal that's all I saw that correlated
Expert:  Reggie Whiddon replied 1 year ago.

Okay no rpm is our problem when. U get hone we will see why we have no signal from crank sensor, might be something from chain installation,

Expert:  Reggie Whiddon replied 1 year ago.

I don't mean no disrespect I've done it myself I put one together and left the wheel that drive sensor out one tine I put one in backwards and it didn't liNE up

Customer: replied 1 year ago.
Just so I'm telling everything if we pull the crank sensor the truck runs badly but does run cause we thought we had a bad crank sensor and it says to check by pulling and see if will start and it does but we have put 3 new ones in and nothing new still doesn't start with installed
Expert:  Reggie Whiddon replied 1 year ago.

I don't see how it runs with it pulled out. When you pull it out look in t h r hole do you see the teeth centered

Customer: replied 1 year ago.
I'll check the teeth when I get home but yes it starts and runs with the crank sensor out but it runs like crap but it does start
Expert:  Reggie Whiddon replied 1 year ago.

That must be a default Chrysler has built in. Impressive. Okay hit me up when u get home.

Customer: replied 1 year ago.
Ok so I'm home and took crank sensor out and teeth r in middle of hole and started while out just sounded not timed of course
Expert:  Reggie Whiddon replied 1 year ago.

Okay I have tried to think of the best way for us to check this crank sensor, I use a lab scope which is the only true way to test it. You do have a voltmeter correct? Your crank sensor it is a 3 wire connector put your voltmeter in between pins 2 and 3 and with key on we want to see 5 volts, if the voltage is off try unplugging your cam sensor see if it comes to 5. The voltage should be within a couple of tenths to 5 volts preferrably 5 on the nose. If not after cam sensor keep unplugging sensors to the 5 volts is there because one problem we could be having is a shorted sensor bringing down the 5 volts. And if we have the 5 volts, go to the pcm disconnect the connectors and check for water or oil intrusion and clean good connections. We have got to get the cranking rpm on that data screen. Let me know I will check in in the morning. Don;t get discouraged we will find this

Customer: replied 1 year ago.
Thanks we will check this latest suggestion. Do you have a wiring diagram you can send us?
Expert:  Reggie Whiddon replied 1 year ago.

Sorry for the delay. The last couple of times I tried to send a wiring diagram I had trouble let me try.

Customer: replied 1 year ago.
We tested wires going to the crankshaft position sensor both with it plugged in and unplugged and it tested 5.2 volts. What does that tell you?
Expert:  Reggie Whiddon replied 1 year ago.

what about when you are spinning it over

Expert:  Reggie Whiddon replied 1 year ago.

Two of those wires give you your five volts the 3rd should have a on off pulse when spinning engine

Customer: replied 1 year ago.
Ok so with the holidays no one has been around to help check while spinning engine over we just went out there and checked and without wiring diagram it's really hard to know which wire should do what but the ones that has 5.2 volts with key on, with engine cranking varied voltage from 2.6 3.2 4.0 5.2 the other nothing what does this mean
Customer: replied 1 year ago.
Checking to see if you received the message above?
Expert:  Reggie Whiddon replied 1 year ago.

Hello Sir yes I just got it I did not see the other one

Expert:  Reggie Whiddon replied 1 year ago.

b Beal
March 6, 20152002 Dodge Ram 1500, Slt 4.7L, V8, VIN N, 16V, SOHC, USA
Camshaft Position (CMP) Sensor

- cam sensor

Replaced Camshaft Position (CMP) Sensor

2Dennis Schick
September 23, 20142002 Dodge Ram 1500, Slt 4.7L, V8, VIN N, 16V, SOHC, USA
Camshaft Position (CMP) SensorReplaced Camshaft Position (CMP) Sensor

3Michael Barbuto
May 7, 20152004 Dodge Ram 1500, Slt 4.7L, V8, Gas, VIN N, 16V, SOHC, USA *
Camshaft Position (CMP) Sensor

- We replace the timing chains and all components 3 months ago. Also replaced both cam and crank sensors with dealer parts at the same time. The dealer cam sensor was defective. Replaced it under warranty and it runs fine now. Remember, only use Mopar sensors!!, Even dealer parts fail sometimes.

Replaced Camshaft Position (CMP) Sensor4Marcel Lamoureux
December 13, 20142001 Jeep Grand Cherokee, Limited 4.7L, V8, VIN N, 16V, SOHC, USA *
Camshaft Position (CMP) Sensor

- Customer Concern : the engine will not start , engine back fires , code P0340 . checked and it have a 5 volts on the orange wire at cam sensor and has good ground at the black and light blue wire but has no 5 volt square wave signal at tan /yellow wire . replaced cam sensor fixed

Replaced Camshaft Position (CMP) Sensor5Phia Yang
April 25, 20071999 Jeep Grand Cherokee, Laredo 4.7L, V8, VIN N, 16V, SOHC, USA *
Camshaft Position (CMP) Sensor

- replaced CKP. Vechicle came back a month later. CMP was also bad. Replaced CMP and no more plroblems. Originally CKP data was bad, as seen through tests. Then vehicle started stalling when hot. CMP had gone bad too. Everything ok now.

Replaced Camshaft Position (CMP) Sensor6***** *****
July 1, 20102000 Dodge Durango, Sport 4.7L, V8, VIN N, SOHC, USA *
Camshaft Position (CMP) Sensor

- No cam position sensor activity on scan tool. Check power supply to sensor and monitor sensor on lab scope, no output. R&R sensor, engine starts and runs normally

Replaced Camshaft Position (CMP) Sensor7Jeff Parsons
June 12, 20152001 Dodge Durango, Slt 4.7L, V8, VIN N, SOHC, USA *
Camshaft Position (CMP) Sensor

- hook lab scope to yellow wire which is cam signal and the other lead to good ground. watch the 5 volt sq

Repaired Camshaft Position (CMP) Sensor8PaddysAuto2
April 6, 20102002 Dodge Ram 1500, ST 4.7L, V8, VIN N, 16V, SOHC, Canada *
Camshaft Position (CMP) Sensor

- Removed connector to check CMP sensor and oil was running out of sensor. Replaced CMP and all is good.

Replaced Camshaft Position (CMP) Sensor9Gary Bonasoro
August 28, 20122001 Dodge Durango, Slt 4.7L, V8, VIN N, SOHC, USA *
Camshaft Position (CMP) Sensor

- Replaced aftermarket cam sensor with one from the dealer fixed it,use factory cam sensors!!!

Replaced Camshaft Position (CMP) Sensor10(+) 11-83Vincent Cuttone
July 24, 20132001 Jeep Grand Cherokee, Limited 4.7L, V8, VIN N, 16V, SOHC, USA *
Camshaft Position (CMP) Sensor

- Installed new timing chains and replaced cylinder heads. no comunication from cam sensor

Replaced Camshaft Position (CMP) Sensor

1Keswick2
March 11, 20152002 Dodge Ram 1500, Slt 4.7L, V8, VIN N, 16V, SOHC, USA
Camshaft Position (CMP) Sensor
Crankshaft Position (CKP) SensorReplaced Camshaft Position (CMP) Sensor and Replaced Crankshaft Position (CKP) Sensor

2***** *****oria
June 13, 20112003 Jeep Liberty, Sport 3.7L, V6, VIN K, 12V, SOHC, USA *
Camshaft Position (CMP) Sensor
Crankshaft Position (CKP) Sensor

- Would loose spark and injector pulse tested CMP and CKP sensors and both would dropped signal replaced both sensors runs great no more stalling problems.

Replaced Camshaft Position (CMP) Sensor and Replaced Crankshaft Position (CKP) Sensor3Jerry Larson
February 22, 20142000 Dodge Durango, Slt 4.7L, V8, VIN N, SOHC, USA *
Camshaft Position (CMP) Sensor
Crankshaft Position (CKP) Sensor

- replaced the cam and crankshaft position sensors , cleared the code road tested several times all is ok now.

Replaced Camshaft Position (CMP) Sensor and Replaced Crankshaft Position (CKP) Sensor4John Fish
September 14, 20122003 Jeep Grand Cherokee, Laredo 4.7L, V8, VIN N, 16V, SOHC, USA *
Camshaft Position (CMP) Sensor
Crankshaft Position (CKP) Sensor

- Replace both cam and crank position sensors with factory replacement parts fixed the P0340

Replaced Camshaft Position (CMP) Sensor and Replaced Crankshaft Position (CKP) Sensor5Keith Hundsberger
June 17, 20152001 Dodge Dakota, Sport 4.7L, V8, VIN N, 16V, SOHC, USA *
Camshaft Position (CMP) Sensor
Crankshaft Position (CKP) Sensor

- NO START CRANKS ONLY CODE P0340 REPLACED BOTH CAM AND CRANK SENSORS, THANKS

Replaced Camshaft Position (CMP) Sensor and Replaced Crankshaft Position (CKP) Sensor6Vitaliy Kondratyev
November 16, 20132003 Dodge Ram 1500, Slt 3.7L, V6, VIN K, 12V, SOHC, USA *
Camshaft Position (CMP) Sensor
Crankshaft Position (CKP) Sensor

- Camshaft Position (CMP) Sensor, Crankshaft Position (CKP) Sensor

Replaced Camshaft Position (CMP) Sensor and Replaced Crankshaft Position (CKP) Sensor7Ron Scrum
November 6, 20102001 Dodge Dakota, Slt 4.7L, V8, VIN N, 16V, SOHC, USA *
Camshaft Position (CMP) Sensor
Crankshaft Position (CKP) Sensor

- Replaced both cam pos sensor and crank pos sensor.

Replaced Camshaft Position (CMP) Sensor and Replaced Crankshaft Position (CKP) Sensor8***** *****
July 21, 20102003 Dodge Ram 1500, ST 4.7L, V8, VIN N, 16V, SOHC, USA *
Camshaft Position (CMP) Sensor
Crankshaft Position (CKP) Sensor

- replacxed ckp, and cmp as a unit. veh ran fine

Replaced Camshaft Position (CMP) Sensor and Replaced Crankshaft Position (CKP) Sensor9Gene Martin
May 5, 20152000 Dodge Durango, 4.7L, V8, VIN N, SOHC, USA *
Camshaft Position (CMP) Sensor
Crankshaft Position (CKP) Sensor

- REPLACED BOTH CRANK SENSOR AND CAMSHAFT SENSOR

Replaced Camshaft Position (CMP) Sensor and Replaced Crankshaft Position (CKP) Sensor10(+) 11-14Tech
August 26, 20132002 Jeep Liberty, Sport 3.7L, V6, VIN K, 12V, SOHC, USA *
Camshaft Position (CMP) Sensor
Crankshaft Position (CKP) Sensor

- camshaft and crankshaft position sensors

Replaced Camshaft Position (CMP) Sensor and Replaced Crankshaft Position (CKP) Sensor1HAMILTON908A
August 6, 20132003 Dodge Ram 1500, ST 4.7L, V8, VIN N, 16V, SOHC, USA *
Crankshaft Position (CKP) Sensor

- Wrong crank sensor installed by customer. Replaced crank sensor and works great.

Replaced Crankshaft Position (CKP) Sensor2Rick Beyer
March 19, 20122000 Dodge Durango, Sport 4.7L, V8, VIN N, SOHC, USA *
Crankshaft Position (CKP) Sensor

- found a bad cam sensor

Replaced Crankshaft Position (CKP) Sensor

3John McCoubry
October 9, 20152000 Dodge Durango, 4.7L, V8, VIN N, SOHC, USA *
Crankshaft Position (CKP) SensorReplaced Crankshaft Position (CKP) Sensor

4EVANSGULF1
October 8, 20151999 Jeep Grand Cherokee, Limited 4.7L, V8, VIN N, 16V, SOHC, USA *
Crankshaft Position (CKP) SensorReplaced Crankshaft Position (CKP) Sensor

5Tony Klaib
June 12, 20152003 Dodge Ram 1500, Laramie 4.7L, V8, VIN N, 16V, SOHC, USA *
Crankshaft Position (CKP) SensorReplaced Crankshaft Position (CKP) Sensor

1Paul Matt Palmer
May 28, 20152002 Dodge Ram 1500, Slt 4.7L, V8, VIN N, 16V, SOHC, USA
Timing Chain

- right timing chain

Replaced Timing Chain2Rob Vicelli
February 6, 20122000 Dodge Durango, Sport 4.7L, V8, VIN N, SOHC, USA *
Timing Chain

- Used borascope go view timing chain through oil fill cap - Cams were not turning - timing chain

Replaced Timing Chain3***** *****
March 12, 20152000 Jeep Grand Cherokee, Limited 4.7L, V8, VIN N, 16V, SOHC, USA *
Timing Chain

- Found timing chain loose upon removal of oil filler neck. Timing had jumped 3 teeth.

Replaced Timing Chain4DICKSFLEETX2
September 26, 20142002 Dodge Dakota, 4.7L, V8, VIN N, 16V, SOHC, USA *
Timing Chain

- Found broken timing chain

Replaced Timing Chain5Frank Constandi
January 13, 20112001 Dodge Durango, Slt 4.7L, V8, VIN N, SOHC, USA *
Timing Chain

- Broken timing chain

Replaced Timing Chain

1Austin Grandel
November 12, 20141999 Jeep Grand Cherokee, Limited 4.7L, V8, VIN N, 16V, SOHC, USA *
Powertrain Control Module (PCM)
133,000 milesReplaced Powertrain Control Module (PCM)

2Joey Ingalls
July 1, 20142002 Dodge Ram 1500, ST 4.7L, V8, VIN N, 16V, SOHC, USA *
Powertrain Control Module (PCM)
157,000 milesReplaced Powertrain Control Module (PCM)

3John Toby
October 5, 20132002 Dodge Ram 1500, ST 4.7L, V8, VIN N, 16V, SOHC, USA *
Powertrain Control Module (PCM)
97,892 milesReplaced Powertrain Control Module (PCM)

1LENSAUTO5161A
February 4, 20152002 Dodge Ram 1500, Slt 4.7L, V8, VIN N, 16V, SOHC, USA
Crankshaft Position (CKP) Sensor Tone Wheel

- SOMETHING WAS WRONG ON EITHER THE INSTALLATION OF THE CAMSHAFT SENSOR INTERUPTOR, OR THE CRANKSHAFT SENSOR INTERUPTOR. ENGINE HAD BEEN REBUILT.

Replaced Crankshaft Position (CKP) Sensor Tone Wheel

2Mike Piazza
November 28, 20122002 Dodge Ram 1500, ST 4.7L, V8, VIN N, 16V, SOHC, USA *
Crankshaft Position (CKP) Sensor Tone Wheel
131,000 milesReplaced Crankshaft Position (CKP) Sensor Tone Wheel

1BARRYSA2
June 17, 20152004 Dodge Ram 1500, Slt 4.7L, V8, Gas, VIN N, 16V, SOHC, USA *
Voltage Reference (VREF) Wiring

- 5v reference (tan/yellow) pin pulled out from PCM connector black

Repaired Voltage Reference (VREF) Wiring2Rick Wilson
September 7, 20121999 Jeep Grand Cherokee, Limited 4.7L, V8, VIN N, 16V, SOHC, USA *
Voltage Reference (VREF) Wiring

- TPS wireing behind head on drivers side rubbing on head bolt

Repaired Voltage Reference (VREF) Wiring

1Cody
March 17, 20091999 Jeep Grand Cherokee, Limited 4.7L, V8, VIN N, 16V, SOHC, USA *

Expert:  Reggie Whiddon replied 1 year ago.

I pasted you a page or two of failure records with your same complaint. These are confirmed repairs, hold on I will get you the wiring diagram

Expert:  Reggie Whiddon replied 1 year ago.

DRI VEA BILIT
Y - GAS

Symptom :
P 1391 -INTERMITT EN T LOSS OF CMP OR CKP

When Monito red and Set Condition :

P 1391 -INTERMITT EN T LOSS OF CMP OR CKP
When Monitored: En gine runn ing or crank ing.
Set Condition: When th e failur e count er reaches 20 for 2 consecut ive tr ips.

POSS IBLE CAUSES
CMP AND CKP OUT OF SYNC

RANKSHAFT POSITION SENSOR - BLACK 3 WAY

CAVCIRCUITFUNCTION

1K24 18GY/BKCRANKSHAFT POSITION SENSOR SIGNAL

2K4 18BK/LB (3.7L/4.7L)SENSOR GROUND

2K4 20BK/LB (5.9L)SENSOR GROUND

3K7 18OR (3.7L/4.7L)5 VOLT SUPPLY

3K7 20OR (5.9L)5 VOLT SUPPLY

CHE CKI NG INT ERMITT ENT CMP SIGN AL WITH LAB WIRE HARNESS INS PE CTIO N
TONE WHEE L/PULS E RING INS PE CTIO N WIRE HARNESS INS PE CTIO N
TONE WHEE L/PULS E RING INS PE CTIO N
CHE CKI NG INT ERMITT ENT CKP SIGN AL WITH LAB CAMS HAFT POSITIO N SEN SOR
CRANKS HAFT POSITIO N SEN SOR

TES T ACTIO N
APP LICA BILITY

1 NOTE: If the vehic le is a NO START you mus t pe rform “EN GINE CRANKS BU T DOES NOT
START” first .
WARN ING: WHEN THE EN GINE IS OPERATING, DO NOT STAND IN A DIRECT LINE WITH THE FAN. DO NOT P
UT YOUR HANDS NEAR THE P ULLEYS, BELTS OR FAN. DO NOT WEAR LOO SE CLOT HING.
Start th e engine an d run unt il operat ing temp is reached. (Closed Loop)
With th e DRBIII ® un der th e Misc. menu , choose th e Set Sync Signa l function an d obse rve th
e Sync Sett ing.
Does th e Actua l Sync Sett ing read in ran ge?
Yes → Go To 2
No → With th e DRB III synchronize Cam an d Crank Position Sensors.
Perform POWERTRAIN VERI FICATIO N TEST VER - 5.

2 Turn th e ignition off.
With th e DRBIII ® as a Dua l Chann el Lab Scope an d Mille r special tool #6801 , backpr obe th
e CMP Signa l circuit in th e CMP harn ess conn ector an d PCM harn ess conn ector.
WARN ING: WHEN THE EN GINE IS OPERATING, DO NOT STAND IN A DIRECT LINE WITH THE FAN. DO NOT P
UT YOUR HANDS NEAR THE P ULLEYS, BELTS OR FAN. DO NOT WEAR LOO SE CLOT HING.
Start th e engine.
Obse rve th e lab scope screen.
Are th ere an y irr egular or missing signa ls?
Yes → Go To 3 No → Go To 6

All

All

191

Expert:  Reggie Whiddon replied 1 year ago.

OPERATION

3.7L

Engine speed and crankshaft position are provided through the CKP (Crankshaft Position) sensor. The sensor generates pulses that are the input sent to the Powertrain Control Module (PCM). The PCM interprets the sensor input to determine the crankshaft position. The PCM then uses this position, along with other inputs, to determine injector sequence and ignition timing.

The sensor is a hall effect device combined with an internal magnet. It is also sensitive to steel within a certain distance from it.

A tonewheel (targetwheel) is bolted to the engine crankshaft ( CKP OPERATION - 3.7L V-6 ). This tonewheel has sets of notches at its outer edge ( CKP OPERATION - 3.7L V-6 ).

The notches cause a pulse to be generated when they pass under the sensor. The pulses are the input to the PCM.

4.7L

Engine speed and crankshaft position are provided through the crankshaft position sensor. The sensor generates pulses that are the input sent to the powertrain control module (PCM). The PCM interprets the sensor input to determine the crankshaft position. The PCM then uses this position, along with other inputs, to determine injector sequence and ignition timing.

The sensor is a hall effect device combined with an internal magnet. It is also sensitive to steel within a certain distance from it.

On the 4.7L V–8 engine, a tonewheel is bolted to the engine crankshaft ( CKP SENSOR OPERATION AND TONEWHEEL - 4.7L V-8 ). This tonewheel has sets of notches at its outer edge ( CKP SENSOR OPERATION AND TONEWHEEL - 4.7L V-8 ).

The notches cause a pulse to be generated when they pass under the sensor. The pulses are the input to the PCM.

5.9L

Engine speed and crankshaft position are provided through the CKP sensor. The sensor generates pulses that are the input sent to the Powertrain Control Module (PCM). The PCM interprets the sensor input to determine the crankshaft position. The PCM then uses this position, along with other inputs, to determine injector sequence and ignition timing.

The sensor is a hall effect device combined with an internal magnet. It is also sensitive to steel within a certain distance from it.

On 5.9L V-8 engines, the flywheel/drive plate has 8 single notches, spaced every 45 degrees, at its outer edge ( CKP SENSOR OPERATION – 5.9L V-8 ).

The notches cause a pulse to be generated when they pass under the sensor. The pulses are the input to the PCM. For each engine revolution, there are 8 pulses generated on V-8 engines.

The engine will not operate if the PCM does not receive a CKP sensor input.

Expert:  Reggie Whiddon replied 1 year ago.

I apologize if some of that did not come through properly.. I have included the factory diagnostic process for your problem as well as pattern failure records along with a general description of the ckt and how it works

Customer: replied 1 year ago.
Thanks and some of the information sent is hard to read. Reading some of the issues you sent, we went and purchased another 3rd one crankshaft sensor this time we bought an original dodge part thinking that the after market ones (like stated a few times in your last message) but the truck still will not start, it cranks but doesn't start.
Expert:  Reggie Whiddon replied 1 year ago.

Okay let me do some more checking today, Have you carefully checked all wiring? One thing we need to be sure of is the pin tension in each connector, this is a very common problem, from testing and plugging and unplugging the terminals inside connectors can become spread open causing them to be loose when connected this causes the circuit to either be open or have a higher than normal resistance. Look at the two halves of the connector and find you something a small drill bit or wire that is the same size as male pin and use it as a tool to check the tension may sound crazy but in about 80 percent of the jobs i take over for people its pin tension.