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Amedee
Amedee, Dodge Technician
Category: Dodge
Satisfied Customers: 24427
Experience:  ASE certified tech advanced level specialist. Wisconsin certified emissions state inspector
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2002 dodge neon: starter relay..fuel injection..key in start position

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2002 dodge neon wont crank
when bypass starter relay and crank have no fuel injection pulse but have spark
wont crank at all with key in start position

Hello!

 

Does the check engine light come on with the key in the on position?

 

Do we have all of our reference voltages to the cam and crank sensor and the tps with the key on?

 

Any codes in the computer?

Customer: replied 6 years ago.

no codes in computer when i bypass to crank i do have rpm goes up to 100 ish

 

Ok... turn the key on and check for voltage at the tps and cam or crnak sensor. Lets be sure that the computer is not being shorted out.

 

If all checks out ok, I can pull you a wiring diagram of the starting circuit and we can pinpoint the problem.

Customer: replied 6 years ago.

i will check those tommorrow

there is also a red dot above check engine that is flashing

check engine light is on because it is in check mode because wont start no codes

i have starting diagram from alldata

power is at ecu pin 31 in the start position

Double check the cam and crank sensor and the tps

 

Let me know!

Customer: replied 6 years ago.
i will let you now tommorrow night thanks again

Sounds good!

Customer: replied 6 years ago.

cam yes

crank yes

rpm 192

while jumpering the starter relay through starter solienoid

fuel pump energizing when turn key on

tps .64 with key in on position

map 4.4 key on

buro 94 key on

auto shutdown relay on while jumpering to crank

red dot above check engine light flashing 1 sec interval

p1685 when jumpering starter relay

thanks for the help let me know

p.s. no power to fuel injectors

 

 

 

SO the code is from you jumpering the relay?

 

No power to injectors? Do we have power to the coil?

P1684

 

Tests/Procedures:

 

1. Check if another key works. If yes, the first key is faulty.

2. If all the keys do not work, a DRB III scan tool is needed to diagnose problems with the Sentry Key Immobilizer System (SKIS).

 

Potential Causes: Defective Ignition Key
SKIS

P1685 Smart Key Immobilizer Module Invalid Key

 

Possible Causes

A theft attempt may have occurred.
Obtain the correct key and attempt to start the vehicle
Do a PCM Reset function to clear the code after engine startup

Customer: replied 6 years ago.
yes we have spark
Customer: replied 6 years ago.

we only have one key and the customer says they only have 1 key

this car worked fine then when cranking because the t belt broke

we through a belt on and was seing if the valves bent which they did and in

checking we starting having this problem we since replaced engine and starter

still have problem

we have a snap on scanner solus if that helps thanks

SO if we have spark, that means the ignition coil has power while cranking. This means the asd relay is engaging. But if the injectors do not have power while cranking, this means we simply have a open or break in the wire or wires from the asd relay to the injectors. Double check for power to the injectors while cranking just to be sure.
Customer: replied 6 years ago.

what about the cranking

shouldnt the car try to start

thanks again for your time your helping alot

YES... it should!

 

DO you need a wiring diagram for the starter?

Customer: replied 6 years ago.
i guess we are going to take to dealership out of ideas
Well, I would be more than happey to try and help you out. But it is up to you.
Customer: replied 6 years ago.

the customer wants his car and we are confused maybe send me a starting diagram

we just wonder if the computer is smoked

Well, we can sure investigate!

 

Here is a wiring diagram. The relay should have two powers going into it with the key on.

 

graphic

 

 

Customer: replied 6 years ago.
in igition start it has two powers but no ignition on
I am sorry, you are correct. Key on we should have one wire with power. Key in the crank position we should have two powers at the starter relay.
Customer: replied 6 years ago.

ok we do so why wont it crank

the computer must be telling it not to crank or to give fuel

Customer: replied 6 years ago.

while trying to start the tan wire at the ecu pin 31 is not going to ground

to engage starter solienoid

also if you can help me in saving some money out of my pocket i will

put some extra money in yours thanks

 

Ok...

 

Not a problem.

 

SO you are saying if you turn the key on and ground this wire at pin 31 at the ecu the engine will crank over....correct?

Customer: replied 6 years ago.

yes will crank have fuel pressure but no injector pulse

 

Well, it can be a bad computer, security system activated or a sensors that is shorted out.

 

Tests/Procedures:

 

1. Check the 5 volt reference at the Throttle Position Sensor (TPS) and the 8 volt to the Camshaft Position (CMP) sensor. If any of the sensors short out, the PCM will not operate correctly.

2. Check the Brown/Yellow wire at pin 76 for a ground when in park. This wire goes to the Transmission Range Sensor (TRS).

3. If the 5 volt reference and the 8 volt power supply are OK, and the Brown/Yellow wire is grounded, the PCM is bad.

 

Potential Causes:

Shorted Camshaft Position (CMP) Sensor
Shorted Crankshaft Position (CKP) Sensor
Powertrain Control Module (PCM)
Shorted Wiring

Tests/Procedures:

1. Check the power to the starter relay on the Yellow wire in the start position.

2. Check the ground to the relay on the Tan wire on pin #31 of the Powertrain Control Module (PCM) with the key turned on.

3. Check the Transmission Range Sensor (TRS) input to the PCM on pin #76 Brown/Yellow wire. It should be grounded in park or neutral.

 

Potential Causes:

Ignition Switch
Powertrain Control Module (PCM)
Starter Relay
TRS
Wiring

Customer: replied 6 years ago.

i going to go out to the garage and check this stuff

if it is a computer and i get a used one do i still need to go to the dealership

or will it work

YES.. The Power Train Control Module replacement requires the vin to be programmed into it before attempting to start.

Here is another no crank Tests/Procedures:

 

1. Make sure the customer is using a Sentry Key Immobilizer Module (SKIM) key with a gray end on it. If not, they need to use the correct key in order for this system to work properly. Make sure there are no other keys on the key ring that have transmitters in them. Make sure the mobile speed pass is not on the key ring, as these are known to interfere with the operation of the SKIM system.

2. If the correct key is being used, try another key to see if the problem continues. If it does not, the original key was the problem, so replace it with a new key and have it programmed by the dealer.

3. Test for fault codes in the SKIM system. Most aftermarket scan tools will not be able to access this module. The factory scan tool, DRB3, will most likely be needed for this.

 

Potential Causes: Defective Key
Incorrect Key
Powertrain Control Module (PCM)
Sentry Key Immobilizer Module (SKIM)
Wiring

Amedee and 3 other Dodge Specialists are ready to help you
Customer: replied 6 years ago.

thanks i got it figured out

the customer gave us another key and it fired right up thanks again

EXcellent!

 

Glad to hear its all fixed!

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