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p2135 p0121 p2101 p0102 p0455 p1682reduced engine powerservice stabilitrack2007 gmc yukon out of warranty
Optional Information: Year: 2007Make : GMCModel: yukonEngine: 5.3 Already Tried: Could it be a faulty ground? what is the location of some of the grounds that should be checked
Any aftermarket accessories?
none
Look at this:
Condition/Concern:
Some customers may complain of an intermittent crank no start, no crank, SES light, and/or security light. Upon inspection, the technician may find low fuel pressure and/or any of the following DTCs: P0030, P0036, P0050, P0053, P0054, P0056, P0059, P0060, P069E, P0102, P0113, P0118, P0131, P0132, P0135, P0137, P0140, P0141, P0161, P0230, P0335, P0341, P0151, P0152, P0155, P0157, P0158, P0161, P0171, P0172, P0174, P0175, P0449, P0452, P0532, P0641, P069E, P1133, P1153, P1682, P2101, P2534, and/or P2544.
Recommendation/Instructions:
If the SI diagnostics do not isolate a cause for this concern, inspect the wiring harness above the front drive shaft for a potential short to ground, near the transfer case side of the front drive shaft as shown below. Repair any chaffed wires by following SI repair procedures.
The harness should be secured to a supporting bracket with a plastic clinch style clip. If the harness has contacted the front drive shaft because of a missing retaining clip, secure the harness to the metal fuel line bracket with a tie strap to prevent a reoccurrence. If the retaining clip is present but contact still occurred, relocate the inboard clip (part of the wiring harness) and tie strap the harness to prevent a reoccurrence.
Here is an example of a harness that is too close:
Experience: ASE Master Technician, L1, Master GM Technician. Over 20 years of bumper to bumper GM experience.
is there anything else, those wires are fine
The only other thing is the PCM grounds, G102 and G103, located on the LS engine block and RS cylinder head. Aside from that, I think you're looking at putting a throttle body on this.
one other thing to note you have to turn it over one complete time with the engine not hitting at all. like its not getting fuel. the second crank it fires right up
Hard to say what that is, you have a slew of codes, ranging from EVAP to MAF to throttle body.... when it doesn't start, that's the time to be there with a scan tool watching the datastream to see what's actually going on.
1 thing I just noticed. When you turn key to on position the throttlebody makes a rattling noise. Also after engine is off there is no fuel pressure. Thanks for helping and I intend to pay you again as well
anyone still up
I believe I have a open/short circuit. With led tester on negative cable and post the light is on. Ive pulled every fuse I can find but the light stays on. Ill pay $100 if someone can help with this tonight
Sorry, had to cut some Z's. Don't get caught up worrying about the rattling noise from the TB. It makes a rapid movement every time you cycle the key, I would anticipate some noise from it. An LED between the battery post and battery cable will light up. Even a test light will light up, there is current moving there, even with the key off. You may have an open/short, but where do you think it is? This truck has ten miles of wire in it, you have to be more specific. If you really want to get into measuring the voltages from the TB, I can provide you with a schematic, and you can take a multimeter to it and pinpoint it.
All of the codes that I research show a probable cause of a short or open circuit. The only way I know to check is with the with the neg cable off and the neg post with an led. If you can help me solve this poblem today ill pay you 300 bucks. Tell me what to start with or some common problems. Shouldnt there only be negative current moving through the ground and not power the led
I think the most important code to get a handle on is P1682. This is the ignition feed circuit to the ECM and TAC modules. This looks like hell, but here is the diagnostic information for that code. I apologize for the way it looks, Internet Explorer is giving me fits.Diagnostic Instructions • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. • Review Strategy Based Diagnosis for an overview of the diagnostic approach. • Diagnostic Procedure Instructions provides an overview of each diagnostic category. DTC DescriptorDTC P1682: Ignition 1 Switch Circuit 2 Diagnostic Fault InformationCircuit Short to Ground Open/High Resistance Short to Voltage Signal Performance Ignition 1 Voltage Powertrain Relay P0689 P0689, P1682 P0690 -- Ignition 1 Voltage-Run/Crank Relay -- P1682 -- -- Typical Scan Tool DataIgnition Scan Tool Data Circuit Short to Ground Open Short to Voltage Operating Conditions: Ignition ON, Engine OFF, Run/Crank Relay and Powertrain Relay are commanded ON Ignition 1 Voltage Run Crank Relay 0 Volts 0 Volts 12 Volts EC Ignition (Powertrain) Relay Feedback Signal 0 Volts 0 Volts 12 Volts Circuit/System DescriptionThere are 2 ignition 1 voltage circuits supplied to the engine control module (ECM). The first ignition circuit is provided by the powertrain relay, through a fuse. This ignition 1 voltage circuit supplies power to all the internal ECM circuits associated with the throttle actuator control (TAC) operation. The second ignition 1 voltage circuit is supplied by the run/crank relay through a fuse, and is used to power the remaining internal ECM circuits. If the ECM detects a voltage difference between the 2 ignition 1 voltage circuits, DTC P1682 will set.Conditions for Running the DTC • The ignition is ON. • System voltage is more than 5.23 volts. • The powertrain relay is commanded ON. • DTC P1682 runs continuously. Conditions for Setting the DTCThe ECM detects that the voltage level difference is greater than 3 volts between the 2 ignition 1 voltage circuits. Action Taken When the DTC SetsDTC P1682 is a Type A DTC.Conditions for Clearing the DTCDTC P1682 is a Type A DTC.Diagnostic AidsThis test procedure requires that the vehicle battery has passed a load test and is completely charged. Refer to Battery Inspection/Test .Reference InformationSchematic ReferenceEngine Controls SchematicsConnector End View Reference • Engine Control Module Connector End Views • Engine Controls Connector End Views Description and OperationElectronic Ignition (EI) System DescriptionElectrical Information Reference • Circuit Testing • Connector Repairs • Testing for Intermittent Conditions and Poor Connections • Wiring Repairs DTC Type ReferencePowertrain Diagnostic Trouble Code (DTC) Type DefinitionsScan Tool Reference • Scan Tool Data List • Scan Tool Data Definitions • Scan Tool Output Controls Special Tools RequiredJ 35616 Connector Test Adapter KitCircuit/System Verification•If DTCs P0685, P0689, or P0690 are set, diagnose those DTCs first.Important: On the scan tool, the Powertrain Relay is referred to as the EC Ignition Relay. •Ignition ON, engine OFF, observe both the Ignition 1 Voltage signal and the EC Ignition Relay Feedback signal parameters on the scan tool. Both parameter values should display no more than 3 volts difference between the 2 parameters. ? If the vehicle passes the Circuit/System Verification test, operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records data list. Circuit/System TestingImportant: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing. •Ignition ON, observe the Ignition 1 Signal and the EC Ignition Relay Feedback scan tool parameter to determine which is less than B+.•Ignition OFF, remove the relay that corresponds to the scan tool parameter that is less than B+.Important: A resistance of 6 ohms or greater in the circuit/underhood fuse block will cause the DTC to set. •Ignition ON, connect a 3A fused jumper wire between B+ and the applicable ignition 1 circuit terminal. Verify that the applicable scan tool parameter displays B+.? If the applicable scan tool parameter is less than the specified value, test the ignition 1 circuit for an open/high resistance. If the circuit tests normal, replace the ECM. •If all circuits test normal, replace the applicable relay.
Diagnostic Instructions
Circuit
Short to Ground
Open/High Resistance
Short to Voltage
Signal Performance
Ignition 1 Voltage Powertrain Relay
P0689
P0689, P1682
P0690
--
Ignition 1 Voltage-Run/Crank Relay
P1682
Open
Operating Conditions: Ignition ON, Engine OFF, Run/Crank Relay and Powertrain Relay are commanded ON
Ignition 1 Voltage Run Crank Relay
0 Volts
12 Volts
EC Ignition (Powertrain) Relay Feedback Signal
There are 2 ignition 1 voltage circuits supplied to the engine control module (ECM). The first ignition circuit is provided by the powertrain relay, through a fuse. This ignition 1 voltage circuit supplies power to all the internal ECM circuits associated with the throttle actuator control (TAC) operation. The second ignition 1 voltage circuit is supplied by the run/crank relay through a fuse, and is used to power the remaining internal ECM circuits. If the ECM detects a voltage difference between the 2 ignition 1 voltage circuits, DTC P1682 will set.
The ECM detects that the voltage level difference is greater than 3 volts between the 2 ignition 1 voltage circuits.
DTC P1682 is a Type A DTC.
This test procedure requires that the vehicle battery has passed a load test and is completely charged. Refer to Battery Inspection/Test .
Engine Controls Schematics
Electronic Ignition (EI) System Description
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
J 35616 Connector Test Adapter Kit
Important: On the scan tool, the Powertrain Relay is referred to as the EC Ignition Relay.
Important: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.
Important: A resistance of 6 ohms or greater in the circuit/underhood fuse block will cause the DTC to set.
Do you have the location of the ignition circuits
They are listed in this schematic. You can do pinout testing right at the UBEC and PCM.
PIT4016B
I have extendended crank times and I also have experieced turn the key on and nothing like the battery is dead. What are the culprits here
All of these things combined has me wanted to look very closely at the run/crank relay and the pwr/trn relay. replace if necessary to be sure they're good.
Could you send me the locations of both. Also how can I pay you more than $28, is there an option for that
In the underhood relay box. They should be labeled just like that. There is an option you can click to pay a bonus, if you'd like. I appreciate that. I will continue to help you out, but bear with me. Very busy here.
Relays replaced, same thing
Check the voltages at the pins for those relays, and tell me what they are.
I replaced both relays and the car is the same. Do you think ECM?
Possibly, but I want to know that you have batt voltage on pin 30 of both relays before I condemn anything.
which pin is 30
never mind its on your schematic
Ok
using a volt meter testing the 30
run crnk relay .1
pwr trn relay .38
black on B- and red on 30 key on position
meter set on 12v
That's not good. What's the voltage on fuses labeled ENG, EMC/THROT CONT, INJ-A and INJ-B?
11.7 on all
That's not possible. Those fuses are powered by the PWR/TRN relay when it's energized. Check your readings again, you can't have .1 volts at pin 30 of the relay and batt voltage at those fuses.
I .05 I 0
I equals the leg of the relay
I 11.71 I 11.71 This is the pwr/trn
- o - .01
-11.70 - 11.05 This is run crank
OK, so you do have batt voltage then? should be hot at all times, not just key on.
yes
OK. Go to the PCM and check pins 19 and 47 on connector C1, which is the black connector. Tell me the voltage there with the key on. Backprobe it, though, the connector has to be plugged in for the reading to be valid.
How do you remove the wire harness off of emc.
There should be a screw in the middle of the connector. But leave it connected, I want you to backprobe it and tell me what the voltage is when you turn the key on and it's all connected. If you unplug it, the voltage will go to zero, because the PCM grounds one of the relays.