LML Injector Circuit Codes 911 help

[exira]

2011 lml duramax
got to start working on the truck again
the truck used to start with a wiff of ether and run smooth
now after replacing 2 injectors i get 2146 2155 and i think it was 2152, also a p0606 which is ecm internal fault.
codes are supply circuit short or open on group 1 2 and 4
WILL BAD INJECTORS CAUSE THESE CODES?
I ohmed the injectors itself and they read like 180k which is within spec
p0606 is maybe being thrown due to connecting and disconnecting batteries?
trying to run thru electrical before i pull the other 6 injectors out bc im thinking something got goofed up seems how it ran smooth and now all of the sudden it is only firing 2 injectors ( unless some injectors crazily wnet bad internally electrically and are throwing the codes)

Thanks,Willy

 

[fc8464]

2011 GMC Truck Sierra - 4WD | Cheyenne, Sierra, Silverado VIN C/K Service Manual | Document ID: 2360342
DTC P2146, P2149, P2152, or P2155
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 DescriptorsDTC P2146Injector Positive Voltage Control Circuit Group 1
DTC P2149Injector Positive Voltage Control Circuit Group 2
DTC P2152Injector Positive Voltage Control Circuit Group 3
DTC P2155Injector Positive Voltage Control Circuit Group 4
Diagnostic Fault InformationFuel Injector Circuits
Short to Ground
Open/High Resistance
Short to Voltage
Signal Performance
Direct Fuel Injector (DFI) High Voltage Supply Cylinder 1
P0606, P2146
P0201
P0606, P2146
P0263
Direct Fuel Injector (DFI) High Voltage Supply Cylinder 2
P0606, P2152
P0202¹
P0606, P2152
P0266
Direct Fuel Injector (DFI) High Voltage Supply Cylinder 3
P0606, P2155
P0203¹
P0606, P2155
P0269
Direct Fuel Injector (DFI) High Voltage Supply Cylinder 4
P0606, P2146
P0204¹
P0606, P2146
P0272
Direct Fuel Injector (DFI) High Voltage Supply Cylinder 5
P0606, P2152
P0205¹
P0606, P2152
P0275
Direct Fuel Injector (DFI) High Voltage Supply Cylinder 6
P0606, P2149
P0206¹
P0606, P2149
P0278
Direct Fuel Injector (DFI) High Voltage Supply Cylinder 7
P0606, P2149
P0207¹
P0606, P2149
P0281
Direct Fuel Injector (DFI) High Voltage Supply Cylinder 8
P0606, P2155
P0208¹
P0606, P2155
P0284
Direct Fuel Injector (DFI) High Voltage Control Cylinder 1
P2146
P0201¹
P1224
P0263
Direct Fuel Injector (DFI) High Voltage Control Cylinder 2
P2152
P0202¹
P1227
P0266
Direct Fuel Injector (DFI) High Voltage Control Cylinder 3
P2155
P0203¹
P122A,
P0269
Direct Fuel Injector (DFI) High Voltage Control Cylinder 4
P2146
P0204¹
P1233
P0272
Direct Fuel Injector (DFI) High Voltage Control Cylinder 5
P2152
P0205¹
P1236
P0275
Direct Fuel Injector (DFI) High Voltage Control Cylinder 6
P2149
P0206¹
P1239
P0278
Direct Fuel Injector (DFI) High Voltage Control Cylinder 7
P2149
P0207¹
P1242
P0281
Direct Fuel Injector (DFI) High Voltage Control Cylinder 8
P2155
P0208¹
P1247
P0284
¹ Misfire DTCs may also set.
Circuit/System DescriptionThe engine control module (ECM) supplies a high voltage supply circuit and a high voltage control circuit for each fuel injector. The injector high voltage supply circuit and the high voltage control circuit are both controlled by the ECM. The ECM energizes each fuel injector by grounding the control circuit and supplying each fuel injector with up to 250 V and 20 amps on the voltage supply circuit to activate the piezo type fuel injectors. This is controlled by boost capacitors in the ECM. During the 250 V boost phase, the capacitor is used to charge the injector piezo stack, allowing for injector opening. The injector is then held open with this high voltage. At the end of the injection event the ECM closes the injector by discharging the injector piezo stack. The ECM monitors the status of the voltage supply and voltage control circuits. The injectors are separated into the following four groups:

• Group 1– injectors 1 and 4
• Group 2– injectors 6 and 7
• Group 3– injectors 2 and 5
• Group 4– injectors 3 and 8

When a fuel injector circuit fault condition is detected by the ECM, the specific fuel injector, or the two fuel injectors in the affected group may be disabled. DTCs for the injector and/or group may set.
Conditions for Running the DTC

• DTC P0606, P1224, P1227, P1233, P1236, P1239, P1242, P1247, or P122A is not set.
• The ignition is ON.
• The charging system voltage is between 10–18 volts.

Conditions for Setting the DTC

• The ECM injector output driver detects an incorrect current on a fuel injector circuit.
• The above condition is present for less than 1 second.

Action Taken When the DTC SetsDTCs P2146, P2149, P2152 and P2155 are Type A DTCs.
Conditions for Clearing the MIL/DTCDTCs P2146, P2149, P2152 and P2155 are Type A DTCs.
Diagnostic Aids

• The electronic control module (ECM) is sensitive to resistance on the injector circuits
• Inspect each connector terminal for loose terminal fit or signs of fretting
• Ensure that the ohm meter is zeroed before making any resistance checks

Reference InformationSchematic Reference Engine Controls Schematics
Connector End View Reference Component Connector End Views
Description and Operation Fuel System Description
Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference Control Module References for scan tool information
Circuit/System Verification

1. Engine Running.
2. Observe the following scan tool parameters:
   • Cylinder 1 Injector Circuit Status
   • Cylinder 2 Injector Circuit Status
   • Cylinder 3 Injector Circuit Status
   • Cylinder 4 Injector Circuit Status
   • Cylinder 5 Injector Circuit Status
   • Cylinder 6 Injector Circuit Status
   • Cylinder 7 Injector Circuit Status
   • Cylinder 8 Injector Circuit Status Each parameter should display OK or Not Run.
   • If any parameter does not display OK or Not Run Refer to Circuit/System Testing.
   • If all parameters display OK or Not Run
3. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
   • If DTC resets Refer to Circuit/System Testing.
   • If DTC does not reset
4. All OK.

Circuit/System TestingDanger: In order to reduce the risk of personal injury, loss of high voltage isolation to ground and higher system impedance, do not attempt to repair any HV wiring, connector, or terminal that is damaged. High voltage coaxial type cables are not repairable. Never attempt to repair a coaxial type cable. The entire cable/harness or component must be replaced. In order to maintain system integrity and personal safety, never attempt to repair any high voltage wiring, cables, or terminals. Performing this procedure on high voltage circuits may result in serious injury or death.

Danger: Before working on any high voltage fuel injection system, be aware of the following procedures:

• Do not make contact with the fuel injection harness, engine control module (ECM), or fuel injectors while the ignition is ON or RUN positions.
• Wait 5 minutes after key OFF to allow the electronic control module (ECM) to discharge before attempting to disconnect or test engine control components.
• Do not use the electronic control module (ECM) case as a ground while jump starting.

Failure to follow the procedure exactly as written may result in serious injury or death.

Note: The following diagnostics must be performed to each injector in the group that the DTC was set.

• Group 1–DTC P2146 with injectors 1 and 4
• Group 2–DTC P2149 with injectors 6 and 7
• Group 3–DTC P2152 with injectors 2 and 5
• Group 4–DTC P2155 with injectors 3 and 8

1. Ignition OFF.
2. Disconnect the appropriate harness connectors at each of the Q17 Fuel Injectors in the group that the DTC set.
3. Ignition ON.
4. Test for less than 1 V between the appropriate Direct Fuel Injector (DFI) High Voltage Supply circuit terminal 1 and ground.
   • If greater than 1 V Repair the short to voltage in the appropriate Direct Fuel Injector (DFI) High Voltage Supply circuit.
   • If less than 1 V
5. Ignition OFF.
6. Disconnect the X1, X2 and X3 harness connector at the K20 Engine Control Module.
7. Test for 0.0 V between the appropriate Direct Fuel Injector (DFI) High Voltage Supply circuit terminal 1and B+.
   • If greater than 0.0 V Repair the short to ground in the appropriate Direct Fuel Injector (DFI) High Voltage Supply circuit.
   • If less than or equal to 0.0 V
8. Test for 0.0 V between the appropriate Direct Fuel Injector (DFI) High Voltage Control circuit terminal 2 and B+.
   • If greater than 0.0 V Repair the short to ground in the appropriate Direct Fuel Injector (DFI) High Voltage Control circuit.
   • If less than or equal to 0.0 V
9. Test for 150K-210K Ω between terminal 1 and terminal 2 of the appropriate Q17 Fuel Injector.
   • If the not between 150K-210K Ω Replace the appropriate Q17 Fuel Injector.
   • If between 150K-210K Ω
10. Test for infinite resistance between each terminal and the Q17 Fuel Injector housing/case.
    • If not infinite resistance Replace the Q17 Fuel Injector .
    • If infinite resistance
11. Replace the K20 Engine Control Module.

Component Testing

1. Ignition OFF.
2. Disconnect the harness connector at the appropriate Q17 Fuel Injector.
3. Test for 150K-210K ohms between terminal 1 and terminal 2 of the Q17 Fuel Injector.
   • If not within 150K to 210K ohms Replace the appropriate Q17 Fuel Injector.
   • If within 150K to 210K ohms
4. Test for infinite resistance between each terminal and the Q17 Fuel Injector housing/case.
   • If not infinite resistance Replace the Q17 Fuel Injector.
   • If infinite resistance
5. All OK.

Repair InstructionsPerform the Diagnostic Repair Verification after completing the diagnostic procedure.

• Fuel Injector Replacement
• Perform the Fuel Injector Flow Rate Programming procedure after replacement of a fuel injector.
• Control Module References for ECM replacement, programming and setup.

 

[fc8464]

Might be a good starting place. Fred

 

[exira]

I started on that, the supply circuit must run somewhere through the fuel control solenoid 1. I can get it barely running on 2 cylinder and the circuits check ok, then when running scanner kicks 4 more out. the solenoid on top of the injection pump with key on is buzzing all the time until i shut key off or pull ecm relay. and when i wiggle that relay i randomly get shorts in the injector circuit also, so im starting from another area. fuse box maybe, i ve had problems with 07 up models having issues inside of them. going to check fpr1 wiring and maybe the injector circuit runs thru there. Thanks a bunch

 

[fc8464]

Fuel Controls– Fuel Injectors

 

[fc8464]

Did you check resistance from the ecm conector for the injectors. this test the circuits and injectors. Only othe thing would be to verify power and grounds going top the ecm. Maybe some one with more experiance will jump in. Fred

 

[fc8464]

power and grounds for ecm

Module Power, Ground, Serial Data, and MIL

https://gsi.ext.gm.com/gsi/showTif.do?image=2396775

 

[exira]

Thanks for the info again, had to pull truck out of shop to work on some other stuff. Will let you guys know what i come up with when i get it figured out!

 

[exira]

Well if anyone did want to know or every experience similiar problem finally got it back in the shop to work on it.

the truck would start and run on 6 cylinder, then give it a little throttle would kick 2 more out, then would kick 2 more out after time. unplugged an injector from the bad group and plugged in a core injector i had, and that group never kicked out!

So, the injectors are internally shorted somewhere, but with the truck off, wiring and circuits check good.

will replace 3 injectors and see how everything turns out!

 

[ikeG]

I will add to this thread since it came up googling my lml DTC.

I had a 2011 in that was shutting down injector 1 & 4, group 1, setting DTC p2146. I found GM TSB PIP5198 that explains harness rub thru up by the egr valve and started there, but found injector 4 control circuit wire rubbed thru against the steel heat shield (picture) on the drivers valve cover.

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