Truck turns over, attempts to start and immediately dies. Also no power door locks, key fob doesn’t work either, as well as no interior lights, or back lights for gage cluster. Checked all fuses and relays come to conclusion it was the body control module... So got a new one, programmed to truck and still have all the same problems. Please help me out, 3 month old little girl and no vehicle to work or for emergency just in case. Thanks everyone who helps me figure this nightmare out!

 

Turn the key on without trying to start it - look for the security/anti-theft indicator light - is it off, on steady, or blinking? Note that it’s normal for it to turn off after a few seconds.

 

It comes on steady then goes rite out.

 

Do you have a code reader for checking for diagnostic codes? They can be stored even if the CEL isn’t on.

Do you have a fuel pressure gauge? I can’t remember if the 4.8 has a valve on the fuel rail for checking the pressure, but if you can check it, pressure should be 55-62 PSI with the key on, engine off. It should hold steady and not lose more than 5 PSI in 1 minute.

Were there any repairs or services done just before this started? Did you fill up at a different gas station or maybe try a different type of fuel (ethanol blend)?

 

I always forget to include this, but in lieu of a fuel pressure gauge, one thing to try is to have a helper crank the engine while you spray carb cleaner or starter fluid into the intake. If the engine starts and stays running as long as you keep spraying, it’s definitely a problem with fuel delivery.

 

Don’t have a fuel pressure gage but that wouldn’t explain no power windows or locks or interior lights rite?

 

You’re right - I got too focused on the engine not starting and didn’t take that into account.

I’m still digging through service & wiring information, but one thing to check if you have power bucket seats is the wiring harness under the driver seat. Some trucks had an issue with the harness getting pinched/chafed between the seat track and frame. A crank no start, inoperative key fob, and instrument cluster issues were a few problems caused by this.

Inspect the harness between the large plug and seat motor - the most common area to get chafed/pinched was a few inches away from the motor.

 

Is there anything else not working? Blower fan, windows, power outlets (cigarette lighter), radio? If it’s got electronic 4wd, are you able to shift into and out of 4wd?

 

Try reading this link, especially in the rust belt: https://www.fixmyoldride.com/Chevrol...pos=3&at_tot=4

 

Bcm is good ecu pcm all those are good, but no power to bcm, just learned that if you push the power window down while cranking it’ll roll down