2000 Silverado C0315 Service 4wheel drive

[snuffyus64]

Hi everyone I have been reading the forum for some info on this truck I have
its a 2000 Silverado it has a service 4wheel drive lamp on. First I thought it was a switch problem which a couple of months ago the light was on I replaced the switch and my light went out. But this time I pulled my switch out and put it in another truck and the switch worked in the other truck.
and visa versa with the other truck switch into the silverado also same problem. I got a code reader and came up with this code c0315 which I did alittle research and found it means there is a ground problem I spoke to a few people and they said its the module under the dash that was bad. I had to save alittle money to be able to purchase this part $345 i got it today and had a fun time changing it out but my 4 wheel service lamp is still on. I dissconnected the battery the ats fuse. let it sit and then even erased the code but it came back. I don't see any wires hanging by the unit. any help would be great if someone had a similar experience

[MT-2500]

Originally Posted by snuffyus64

Hi everyone I have been reading the forum for some info on this truck I have
its a 2000 Silverado it has a service 4wheel drive lamp on. First I thought it was a switch problem which a couple of months ago the light was on I replaced the switch and my light went out. But this time I pulled my switch out and put it in another truck and the switch worked in the other truck.
and visa versa with the other truck switch into the silverado also same problem. I got a code reader and came up with this code c0315 which I did alittle research and found it means there is a ground problem I spoke to a few people and they said its the module under the dash that was bad. I had to save alittle money to be able to purchase this part $345 i got it today and had a fun time changing it out but my 4 wheel service lamp is still on. I dissconnected the battery the ats fuse. let it sit and then even erased the code but it came back. I don't see any wires hanging by the unit. any help would be great if someone had a similar experience

You are right on ground problem.
But several things can cause ground problems.
Connections and plug ins and wiring or dirty ground ends.

Did the code clear and come back or never clear?
Light go out and then come back?
First thing.
Go over grounds with a volt ohm meter real close.

Did the 4W work or try to after clear code?
Is it setting a B-315 or the C0315 code?

[snuffyus64]

the code cleared but came on a few seconds after it was cleared.
it never tried to work I never got lights on the switch panel.
I have a schematic on the truck and Im going over the grounds now let you know if I find anything thanks for your help.

[j cAT]

your co315 dtc is the encoder motor ground circuit has a problem. this is the black wire on connector C2 terminal C...this goes to the ground G110..this should be by the left front body mount ...follow the wire harness from the encoder motor it is allong this harness...

this code is generated because the ground is showing a voltage ...

too bad you spent so much for that control module ..not to many issues with that ..