I have a 2007 Suburban 5.3L 4WD with roughly 178k miles. It is is fairly good condition, and runs well. The last week or so a strange thing is occurring. When I turn the key, I get NOTHING, no crank, no click. The dash lights all fade or go completely out. It will then start a second or two later (sometimes longer), and seems to run fine, but the temperature controls all reset back to 74 degrees. The gauges all seem to read normal.... Had the battery, alternator, and starter tested, and all came back good..... I would think with the temp controls resetting that it was a battery problem, but wouldn't that also affect other electrical items and reset them as well? I am stumped and and would appreciate any ideas of where to start with something like this.

J

 

Get codes read and post them here. Might be intermittent corrosion issue or loose connection

 

O.K.

I hooked up my code reader and found the following:
C0242-00 - Power Train Control Module Indicated Traction Control
U0073-00 - CAN Bus Communication
C0899-00 - Control Module Power Circuit
C0900-00 - Control Module Power Circuit

 

U is a network issue
C is a chassis issue

The best guess are fluctuating electrical voltages in your, Chevy. Probably going to need to chuck the PTCM or ECM after you inspect it and do some more testing.

 

Read this: https://www.fixmyoldride.com/Chevrol...pos=3&at_tot=4

Especially in rust belt areas, this is a common problem. This link may help as well: https://www.tahoeyukonforum.com/thre...stions.111196/