Bizarre electrical problems '99 Rodeo

I have had a series of really strange electrical problems - HELP! At first the horn would come on at odd times and stay on until I pulled the fuse. This happened once while driving and once while parked over night. Next, the wipers come on nearly every time I start the car. They stay on for 10 to 60 seconds and then park themselves. At other times, the speedometer and tachometer go to zero and stay (until I hit a bump once). Lastly, only one time after some of this happened, the engine would cut out and then come back, like momentarily pulling a coil wire. This went on for about 15 miles and then resolved itself.

I have read of ground and alternator problems, but they seem to be gen 1 Rodeos. I cleaned and tightened the battery to alternator and the battery to body ground and even added an additional ground from the engine block to the body.

This seems like a floating ground or loose connection, but I can't find it. HELP!

One more thing...while the horn fuse is out, all lights seem to waver. Everything from headlights to dash lights sort of dim and brighten in a twice a second cycle. This may just be a symptom of a circuit being open, but thought it mean something to someone.

RBOC

horn concern is it on off on off like an alarm?

your wiper concern is your alarm/relay module very common concern

last but not least. Assuming this is a v-6 this should help.
Start the vehicle and wiggle the harness that is at front the drivers side valve cover the big one dont be scared to tug it hard you are trying to find a broken wire if the vehicle dies you will need to open the engine harness there are two wires that are red/white you should find one of them to be broken but not visually you will have to tug on each one of them individually give them a good tug hard enough to break the insulation on the wire you should feel one of them stretch then break if this is where the problem is I suggest soldering the wire and insulating with heat shrink (radio shack) will have what you need. But try this first check the 4 connectors under the P/S resivoir make sure all of them are free of the green stuff clean if needed and use a small pair of needle nose pliers give all pins a slight twist to ensure good tight connection when you reconnect them.

let me know if this helps

Thanks 2eyefichclaw (got to figure out where some of these names come from!)

The horn is solid, not off & on laike an alarm. I first thought the wavering lights were part of the alarm flashing the lights, but decided that was not the case. The condition has moved to wipers-only for the past several days. I have an alarm module pulled from an amigo waiting for me to pick up.

The book says pull the dash. Can I change the module (even if the new module isn't fully installed) without pulling the dash?

Also, I'll look at the wiring harness this weekend. Again, thanks for the information!!!

do not pull the dash
remove the glove compartment door the module is mounted on a bracket to the right side you should be able to see it (flashlight) there are two phillips head screws holding it in they will be very tight push hard on the screwdriver #2 to prevent stripping the heads out after they are out you will have to slide it up then you can remove it
not so bad huh. The fun part is getting the new one in. There is a horn relay built into the relay module so this may also take care of the horn issue

there is more than one module design for these vehicles be sure you get the right one I belive theres only two models one of them is red the other is grey so check yours before purchasing another

2eye, you've really helped me before so here goes. I have a similar horn problem in my 98 2wd 5-spd Rodeo. Horn will sound at any time, whether the car is running or not and will go off if I hit the horn button on the steering wheel. I now just run with the underhood fuse pulled all the time, so no horn (and nothing to tell you when you lock/unlock the doors-Grrrr). I have pulled the airbag module (dumb, I know) and tried to clean the relay in the steering wheel (it's behind the airbag) as well as possible, thinking it may be corrosion in there from living in SoCal the last five years, but this didn't work. Any thoughts?

sinner


Thanks 2eyefichclaw (got to figure out where some of these names come from!)

The horn is solid, not off & on laike an alarm. I first thought the wavering lights were part of the alarm flashing the lights, but decided that was not the case. The condition has moved to wipers-only for the past several days. I have an alarm module pulled from an amigo waiting for me to pick up.

The book says pull the dash. Can I change the module (even if the new module isn't fully installed) without pulling the dash?

Also, I'll look at the wiring harness this weekend. Again, thanks for the information!!!