How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Daniel Wilson Your Own Question
Daniel Wilson
Daniel Wilson,
Category: GMC
Satisfied Customers: 5558
Experience:  Owner at DJ Wilson
Type Your GMC Question Here...
Daniel Wilson is online now
A new question is answered every 9 seconds

My sisters 2006 GMC Sierra Hybrid is not running. Car doesn

Customer Question

My sisters 2006 GMC Sierra Hybrid is not running. Car doesn not turn over or crank. I checked the 42 volt hybrid batteries, and they are good. Borrowed Tech2 from a friend and got these codes:
Any help would be appreciated.
Submitted: 1 year ago.
Category: GMC
Expert:  Daniel Wilson replied 1 year ago.

Hi my name is***** will try to help.

Trouble Code Fault Location

P0036 Heated oxygen sensor (HO2S) 2, bank 1, heater control -circuit malfunction

Probable Cause:

Wiring, HO2S, ECM

Trouble Code Fault Location

P0050 Heated oxygen sensor (HO2S) 1, bank 2, heater control circuit malfunction

Probable Cause

Wiring, HO2S, ECM

P1626 Engine control module (ECM) -fuel enable signal lost

Causes: Wiring, poor connections, immobilizer control module, ECM

U1026 Transmission control module (TCM)/four wheel drive control module, CAN data bus communication malfunction

Causes: Wiring, BCM

U1064 Body control module (BCM), CAN data bus communication malfunction

Causes: Wiring, BCM

Expert:  Daniel Wilson replied 1 year ago.

P1A213 I have no listing for. Test all your fuses and relays and inspect the harness and connector pins for corrosion or damage causing a loss of power or ground to the ECM and BCM. Let me know

Customer: replied 1 year ago.
First thing we checked was all the fuses and relays. I checked the connections this weekend to modules. We checked the voltage going to the SGCM and that was fine, however the three orange cable from the SGCM to the motor are not showing voltage. I remember reading online somewhere they should be evenly distributing 36 volts. Are you familiar with this type of hybrid, anyway to diagnose what the issue might be.
Expert:  Daniel Wilson replied 1 year ago.

This is going to be very difficult to diagnose without the diagnostic GM software connected to the vehicle to talk to the modules and check the live data and parameters.

Here is a flow chart for a no crank/ no start:

•Ensure the Energy Storage Battery Pack is fully charged.

•Ensure the 175A Hybrid fuse in the under hood fuse block is functional.

•Always perform the Hybrid Battery Service Disconnect/Connect before diagnosing or servicing any PHT systems.

•It is imperative that the 3-phase cable connections are clean and the fasteners are torqued to specifications. Torque specifications are 14 N•m +/- 2 N•m at the starter generator, and 15 N•m +/-2 N•m at the SGCM.

1.Turn the ignition OFF.

2.Disconnect the 3-phase cable from the Stator (Electric Machine). . Test for shorts between the stator connections, and to chassis ground.

⇒If a short is confirmed, replace the Starter Generator Stator.

3.Disconnect the 3-phase cables from the SGCM. . Test the 3-phase cables circuits for shorts between cables, and short to chassis ground.

⇒If a short is confirmed, replace the 3-phase cables.

4.If no trouble found, replace the SGCM.

Information/ Operation