I have two grounds at the rear of my blazer that I don't know exactly where they are supposed to go from and to. But I have no licence plate lights, headlights dont work right, stereo doesn't work and a few other things. Im sure it's a ground but not sure which one or ones. PLEASE HELP

 

What do you mean that you have grounds that you don’t know where that are supposed to go? Black wires coming out of harnesses not connected to anything? Ground bolts on the frame with no wires attached? Something else?

What do you mean your headlights don’t work right?

The items that you listed have unique power and ground circuits so we need to tackle them one at a time.

Lets start with the license plate lights. Check the Trl Prk Fuse 10A in the Underhood fuse box. If good, check for 12V at the bulb socket. If good ground the bulb socket ground with a wire to the frame.

For the stereo start by checking the RDO Bat Fuse 19, 10A in the I/P fuse block.

George

 

Well heres the deal.the head lights work on the running light setting and the running lights on the head light setting. They are backwards. Not the switch, I have tried 3 different new ones. The tcm fuse you talked about if I pulled it and put it back the headlights and radio would work. I replaced the bcm and still no change. The tail light wiring seems to not look hooked up right. I have a pigtail the t's to the licence plate lights then the one part plugs into the connector on the frame by the diff and a black ground wire comes out and is grounded to the frame. Then it all connects and runs into the main harness up to the relay box under hood. But there is also a large 12 or 18 pin connector in the middle of the licence plate light wires and I dont think its a trailer plug and then another cluster of 5 wires that are not connected to anything. Also a ground back there from body to frame. Now besides the lights and radio, the button for the back gate stopped working. Gas gage doesn't work, rear wiper isn't working and horn not working. I have replaced all relays. New battery. New bcm, all new dash switches. Cleaned all connections. Im at a loss. Im sure almost ars a ground . Am I on the right track

 

I did not mention a TCM fuse, which fuse box is that in and what is it for? You pull and replace that fuse and your reversed headlamp/running lamp function corrects itself and the radio turns on? If I have that right then you may have some corrosion/wiring issues near a fuse box.

whats wrong with your tail lights?

Yes a ground can cause problems but this list of issues uses multiple grounding points. I have given you some diagnostic steps which start with checking power to the problem circuits, please complete them and report back. Do you have a digital multimeter? We have to track down and isolate each one of these issues and some of them are probably not related.

Have you given me the entire list?


George

 

Also, there is a group of four wires that are tucked up in the back near the spare tire that are unconnected and used for a future trailer wiring connector. They are brown, yellow, Dk green and lt blue.


George