Electrical issues

[chevywood]

Ok guys, I am having several issues on my 1984 m1008. It started because I was always having to charge the batteries. Did some readings and never had a gen 2 light and no power to gen 2 exciter wire. I did some dash work, actually put in a whole new gauge cluster as the previous one was missing a ton of lights and tabs. Now, both gen lights come on when starting the truck, however, the gen 2 light will not go out, it is always on. From what I am understanding, I either have a bad battery or a bad alternator. As for some of the other issues, the wait light on the dash stays on for about 30 minutes, the low coolant light is on and will not go out. The coolant level is full so I don't know what might be causing this. Also, when I turn on the headlights, the right blinker light dash light is on. The blinker will still work, but when not using the blinker the light stays solid. The last issue is that my heater does not get very warm at all. Any help with these issues would be greatly appreciated.

 

[cpf240]

As they say here "...if its electrical, clean it"

Fist of all, have the batteries load tested and fully charged. Always start troubleshooting electrical problems with good, fully charged batteries.

For the turn signal thing, and possibly other issues you mention, find and clean every single ground connection you can find. Check the bulb sockets for all the turn/marker/brake lights. Clean everything.

For the GEN 2 issues, do the above and also test the output with a meter. Have the batteries load tested. Perhaps pull the alternator and have it bench tested.

For the Wait light, make sure your GP system is working. I'd suspect bad glow plugs and / or a bad glow plug relay. Another possibility is a bad glow plug engine temp sensor.

For these, and other issues, read the troubleshooting section of the TMs, they will help narrow down the cause(s) and be an education as well.

Good luck!

 

[tankie88]

My low coolant light was always on as well.When i had a look the plastic holder was full of water which shorted the card out and it fried.

 

[Barrman]

The low coolant sensor is on the passenger side of the radiator. Follow what the -20 says and ground the wire. That is how you test it.