ok, oops, my first post said I see an electrical type sensor at the rear of the tranny -- went to replace it, nope, it was just wiring for something else. So, I ASSUME the sensor at the top of my rear differential is the VSS sensor, which I already replaced?


I went looking for the battery saver relay -- checked the owners manual. It showed a 15 amp fuse for it inside the cab fuse block. I looked under the hood, saw a couple of big relays and several "half relays". I checked the owners manual, none of the items in the fuse block under the hood relate to the battery saver relay.


Can anyone steer me in the right direction?


Also, I called the dealer about a new GEM -- $358. How about a wrecking yard if I need to replace it?

 

14 bolt pan takes the rear differential sensor. 20 bolt pan takes the one on the tailshaft. It depends on your transmission. It can be in either place depending on your particular vehicle. In your case, you must have a 14 bolt pan.

 

Yes 14 bolt pan -- so I've already replaced the VSS apparently -- still not sure about the battery saver relay. Maybe I should reset the codes and drive it awhile and see what comes up. As wOlvez said, maybe it's the GEM

 

That is quite possible. The GEM's are really taking a beating this year if you look at the questions being posted. If you pull a GEM, used from a yard, you need the very same number you have on your truck. It could be upgraded, so pull your number and run it on the net for updates. This way you know for sure you are getting the right parts. The GEM controls so many operation in the truck, it is the 2nd brain actually, after the main computer.

 

Measure Voltage between Battery Saver Relay pin 5 and ground. If there are no voltage install a new relay. If there is a voltage the end of diagnostic tree will end to Install a New GEM or New Central Junction Box.

Pin 5 is nearest on the side that has 3 terminal.

 

W0lvez -- the problem is I don't know where the battery saver relay is.


I went looking for the battery saver relay -- checked the owners manual. It showed a 15 amp fuse for it inside the cab fuse block. I looked under the hood, saw a couple of big relays and several "half relays". I checked the owners manual, none of the items in the fuse block under the hood relate to the battery saver relay. One big relay, according to the owners manual, is Fuel Pump Relay -- the other big relay is Powertrain Control Module Relay. So I am still lost as to what to do.

 

Pretty sure that's under the dash. However, it might not be in the fuse block.

Iduno, I'd look up the diag, but I'm not in the house, - In the hammock outside contemplating yard work.

AK has been handy with diagrams lately, maybe he'll throw one up if you ask him.

 

In the Central Junction Box (Driver Side Fuse/Relay Compartment) 2nd small relay from the top

 

Did you find it?

 

Yes, just opened the cover, I see two smaller relays, then some larger ones.


The owners manual shows that relay to be the Powertrain Control Module, and Cluster.


But I touched the leads of the multimeter to the number 5 slot (after pulling the relay), as shown on the relay, and the other to several pieces of metal on the dash area, and no reading was given on the multimeter. I heard no click when removing the relay, and heard a light click when installing it. (when pulling it, I kind of banged the dash which could have hidden any clicking when removing)


Then tried connecting one lead of the meter to the #5 of the relay, and touched ground with the other lead, and did get a reading.