Codes b0770,b0775,b0780,b0785 indicator circuit short to ground/open

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

wsteele

Full Access Member
Joined
Dec 26, 2020
Posts
1,731
Reaction score
2,350
just seems strange that there would be no other codes, I have the service manual in pdf but it's not linkable so it makes it very difficult when it say's to reference "x" and you cant go directly there and it has 10,000+ pages :flame:
I feel you, the manual seems like it was written so a programmer could code for a robot, versus being written for a human to use effectively.

In the transfer case debug section I looked at, the only codes are B07xx and C03xx, no U codes at all. The one exception is a B2725 which pertains to the switch circuit, if that code is stored, then it sends you down a path to debug the switch (and all paths seem to lead to the switch being replaced if the wiring checks), otherwise it all seems to be centered on an endpoint of replacing the shift control module.
 

exp500

Full Access Member
Joined
May 14, 2017
Posts
1,860
Reaction score
1,714
Yeah that really sux on the pdf manuals, have to keep a notepad handy.
What you will probably wind up doing is a process of elimination by the troubleshooting guide and codes list. The pick the most likely candidate and further investigate with meter.
 
OP
OP
U

uk tahoe

TYF Newbie
Joined
Jul 25, 2012
Posts
29
Reaction score
15
Location
Uk
Right so with new and old switch I can hear the actuator working but on the switch itself I don't get the yellow indicator lights to let me know that in in that mode , the red N lights up on start up .
 

wsteele

Full Access Member
Joined
Dec 26, 2020
Posts
1,731
Reaction score
2,350
Right so with new and old switch I can hear the actuator working but on the switch itself I don't get the yellow indicator lights to let me know that in in that mode , the red N lights up on start up .
Pretty much everything I have points to the TCSCM. In the book it says when installing a new TCSCM you will need to program it and do a clutch reset (not sure what the clutch reset is, but likely both can be done with a Tech 2).
 

Forum statistics

Threads
132,247
Posts
1,864,704
Members
96,797
Latest member
Dave00
Top