2007 LTZ issues

[Beavis]

Hello all, I have a 2007 Tahoe LTZ and am having strange electrical issues, just looking for some advice. Purchased used last year with 120,000 miles, wife was driving the other day and it had a no start in a parking lot. As I was headed to get her and look at it, she got it to crank. Since then it’s been in the yard with the following issues, all intermittent:

-no start
-instrument cluster working/dying at random
-slow power drain
-all warning lights like service 4wd, service tpm, etc on and off at random
-remote key/remote start intermittent
-intermittent radio and display blackout/no sound
-once while running and in park the transmission bucked like someone had bumped into the back at around 5-10 mph

I’ve checked grounds, fuses, the RKE module in the back D pillar, replaced battery, I’m leaning toward BCM or possibly the front air bag sensors, fairly sure one or both of those are bad. Could the airbag sensor cause a random laundry list of electrical issues or am I looking at one of these modules?

Thanks in advance for any advice!

 

[Doubeleive]

Hello all, I have a 2007 Tahoe LTZ and am having strange electrical issues, just looking for some advice. Purchased used last year with 120,000 miles, wife was driving the other day and it had a no start in a parking lot. As I was headed to get her and look at it, she got it to crank. Since then it’s been in the yard with the following issues, all intermittent:

-no start
-instrument cluster working/dying at random
-slow power drain
-all warning lights like service 4wd, service tpm, etc on and off at random
-remote key/remote start intermittent
-intermittent radio and display blackout/no sound
-once while running and in park the transmission bucked like someone had bumped into the back at around 5-10 mph

I’ve checked grounds, fuses, the RKE module in the back D pillar, replaced battery, I’m leaning toward BCM or possibly the front air bag sensors, fairly sure one or both of those are bad. Could the airbag sensor cause a random laundry list of electrical issues or am I looking at one of these modules?

Thanks in advance for any advice!

ohm test the battery cables, and do a voltage drop test from battery to starter, clean up the mega-fuse connections
these battery cables can corrode from the inside and look fine on the outside.
all of your symptoms can be directly related to poor electrical power/ground.
check fuse box
check ecm harness
you could also try a "big 3" upgrade to see if that helps at all.
bcm is at the bottom of the list
air bag sensors are likley a no, there is no power applied to them when the vehicle is off, so even if they were bad it would just throw a airbag light/code when the key is in the run position
transmission bucking if not related to everything else could be the harness there is a tsb on it, could also be the maf

 

[Beavis]

ohm test the battery cables, and do a voltage drop test from battery to starter, clean up the mega-fuse connections
these battery cables can corrode from the inside and look fine on the outside.
all of your symptoms can be directly related to poor electrical power/ground.
check fuse box
check ecm harness
you could also try a "big 3" upgrade to see if that helps at all.
bcm is at the bottom of the list
air bag sensors are likley a no, there is no power applied to them when the vehicle is off, so even if they were bad it would just throw a airbag light/code when the key is in the run position
transmission bucking if not related to everything else could be the harness there is a tsb on it, could also be the maf

Thank you, I’ll proceed with those. Have a great day and Happy New Year!

 

[budman1974]

I also have a 2007 tahoe ltz. I just got through battling the same issue! randomly, accessories would stop working, and finally, abs/trac control.and brake lights came on,while driving. I shut the truck off, and it would not restart. I also lost my fuel guage and gear position display, truck would not crank! To make a long story short, check/unplug the z55 air suspension computer above the spare tire under the truck! unplug it and attempt to start. if it starts, you will need a new or used suspension control computer, because the hi speed can datalink passes through it. I also needed a new left instrument panel fuse/junction block, (on the interior firewall near the ebrake mechanism) this is the junction for all comunication wires in this truck! When the suspension module shorted, it fried this junction block! Just make sure you get the correct part number for both the suspension computer and the junction block, they are 2007 only!

 

[Geotrash]

I also have a 2007 tahoe ltz. I just got through battling the same issue! randomly, accessories would stop working, and finally, abs/trac control.and brake lights came on,while driving. I shut the truck off, and it would not restart. I also lost my fuel guage and gear position display, truck would not crank! To make a long story short, check/unplug the z55 air suspension computer above the spare tire under the truck! unplug it and attempt to start. if it starts, you will need a new or used suspension control computer, because the hi speed can datalink passes through it. I also needed a new left instrument panel fuse/junction block, (on the interior firewall near the ebrake mechanism) this is the junction for all comunication wires in this truck! When the suspension module shorted, it fried this junction block! Just make sure you get the correct part number for both the suspension computer and the junction block, they are 2007 only!

Thanks so much for following up with your experiences. Super helpful for others.