electrical wizards needed

[Diesel Dan]

Help my 89 5 spd that i sold to my nieghbor is having electrical glitches.



Here is the skinny.



wont start, no clicks nothing, then pulled out the headlight switch and veroom she starts. all of a sudden the amp meter on the dash is now working(hasn't worked in a year or so but the system was charging verified by the headlights getting brighter over idle) shut it off and is dead again. now no headlights fiddled with it and got headlights to work and it will start again. obviously this is strange as these two arn't related or are they? keep fiddling and now cant get headlights or starting. was thinking it was in the ignition switch but that shouldn't relate to the headlights or headlight switch.



where do i go from here???



thanks in advance



DD

 

[ETOBICOKE]

Wiring Problem

Try the fuse links, possibly the ignition one has buned out and shorted into the wiring harness. The vehicle lighting and ignition switch are totaly seperate except for the turn signals. Could also be some overheated wiring all shorted together. If you need some diagrams send me an email.

Neil

 

[Diesel Dan]

Thanks Neil

where are the fuse links and what do they look like and i will check them out



Thanks

DD

 

[ETOBICOKE]

Fuse Links

Dan look on the driver's side inner fender, they come out from the wiring harness near the heater relays. The fuse links are pieces of rubber insulated wire spliced into the harness with heat shrink tubing. Just give each one a stretch, if it's bad it will come apart. If it's bad you need to replace it with the same size, it's available at auto parts stores.



Neil

 

[DieselDoghouse]

Gotta dump in my . 02 no matter how stupid. Since I was a kid (and cars were alot less reliable) whenever we had a no-start that resolved by turning on the headlights we always looked for a junction problem first: Check your battery terminal clamps and posts for ANY corrosion first. If there's none then I'm gonna guess it could even be internal in a battery buss. Here's why: the corrosion acts like a large resistor and will not pass cranking current, but the more controlled draw of the filaments starts to burn through the bridge and re-establish conduction, then the starter spins. The ammeter? maybe reading current in/out of the battery and so no charge current no reading. Connections are funny like that. Had a comm receiver at a radio station when I was a kid that would only output for 15 seconds then stop - unless you put an ice cube (in a paper towel) on the chassis - cold solder joint in the BFO circuit would heat and open during transmitting.

 

[Dale Reed]

You guys are talking "ampmeter" because you added them to your trucks. Right? My truck came with a voltmeter from the factory and I assume yours did also.



I sure wish I knew what the marks meant on the voltmeter. It seems to me that the volts are less than they used to be going down the road but maybe I do not remember correctly.

 

[scott4glamis]

just a thought try jiggling the wires that attach to the ignition switch, heard of some vibrating off!!!!!!!wonder why!!!

 

[Deezul1]

The very first thing to do on any dc current problem is to CLEAN the battery connections very good. Its amazing how many problems go away after that. If the cables are really old they will corrode inside the insulation at the battery end and sometimes be so bad it gives trouble there also.

Good luck

John

 

[Lil' Dog]

My 89 died on me with the same problem. The solution was that the + lead going to the starter was rotted in the center at the battery terminal and had to replace it. As the previous posts said, juice for the radio and stuff, but not enough for the starter. Maybe replace both cables with new ones, or at least the clamp ends.



The 89's did come with the ammeter with the C/D scale.



J-eh

 

[JohnE]

I had a vehicle where all the accessory and ignition power came through the headlamp switch. A loose wire between the H-light switch and ignitions switch produced roughly the same results. Not sure if this is the same in the original CTDD



-John

 

[Dale Reed]

... The 89's did come with the ammeter with the C/D scale...



Thanks Lil' Dog, that explains a lot. Like references in the Shop Manual to the Ammeter.



My mechanic says that my alternator is broke, so he has ordered a NAPA rebuild and will be installing it along with a new regulator tomorrow. The truck would not start this morning because the battery was not charging most of the way home down the freeway last night. The alternator only lasted a few years and cost a pretty penny. I guess you all have replaced your alternators with stronger tougher ones but anyway I should be dieseling again tomorrow.

 

[Diesel Dan]

thanks for the help

problem solved but still scratching my head although the connection between the battery post and the + lead looked clean and was service 6 months ago when the battery was replaced, it was not getting a good connection. determined this when we tried to start it after a few days and we got arking between the post and cable. Pulled off the cable and found no corrosion but the post looked like it was a wood post eaten by termites( arking inside) the cable was tight on the post and no corrosion but bad connection????????????? (twilight zone material) has anyone heard of this and should i do anything more to the connection to prevent this from happening in the future. (besides the cleaning that we di to get the truck to start)



Thanks for all the help, suggestions and especially to Neil C for e-mailing all the drawings( which i will retain for possible future usage )



This is what it is all about



DD

 

[JLEONARD]

I had a similar experience a year ago when I had an F150 (I was looking for a CTD). The neg battery post on a brand new AC Delco was leaking causing my terminal to corrode... it ate thru 75% of the clamp bolt in 6 months.

I complained to a friend of mine who is an AC Delco sales rep. He did some digging and discovered that Delco had made a bunch of batteries with what he called porous material (probably made in the far east in my opinion). That was allowing the terminal to leak.

Your may not be the same situation but the what you describe does not surprise me... .companies will do most anything today to save $$ and not always in our best interest.