Electrical problems

[tinyfootprints]

I've had some transmission problems this past week that have been getting progressively worse and I now suspect it's an electrical or sensor related issue but would appreciate any input. I've hooked my code reader up several times but so far no codes have been thrown.

 

- 2007 Sierra SLT crew cab, 4wd, 138,000 km

- Problem started a couple weeks ago when I would put the truck in reverse and it would slip out of gear when I hit the accelerator. This happened very intermittently.

- Last week I had a couple of instances where I was stopped at a red light. Light turned green and when I hit the accelerator, the truck would not get out of first. Speedo/rpm gauges were working fine though. This happened a couple times last week.

- Was driving last night and it started raining steady and same problem - at a red light / on green light truck would not get out of first. This time a 'check traction control' message flashed as well. I stopped at a gas station and turned off the truck. When I turned it back I got the same error message and the ABS light was on as well. When I started driving only the battery gauge was working, all other gauges (speedo/rpm/fuel) were at zero and the truck was stuck in first. Pulled into my driveway 10 mins later and turned off the truck. When I tried to turn it back on the engine wouldn't start. Not even the 'clicking' sound you get when you try to start but your battery is dead. Dash lights came on but no sound from the engine at all. Tried starting again about a half hour later when it stopped raining and it started with no problems, gauges worked fine, tranny was ok, etc.

 

Would appreciate any input you can provide. Thanks!

[Carder09]

Sounds like a pcm issue. Wish I could.be more helpful but its a start I suppose.

[waumo1]

Eliminate the easy things first. Check all your battery cables and grounds. Especially check grounds to the body, frame, engine, etc and especially if there is one near the PCM. Take them off and clean the connections.

[PhilB]

It is most likely your battery. If it is the original, you should replace it. What is probably happening is your battery is not feeding enough voltage to the rest of the vehicle. That causes the ECM, BCM, and a myriad of sensors to not operate correctly.

[tinyfootprints]

Thanks for the advice. I'm going to check my grounds and install a new battery today.