'97 Rodeo 4WD auto 3.2 liter.
To the regulars, you may know that I've been attempting to self diagnose the rear ABS fault.
To everyone else, I've been trying to avoid paying $85 an hour to the Isuzu dealer.

Well, now I've pulled a beauty. After having no luck trying to get ABS codes by grounding the diag wire at the ABS module I've created a bigger problem. (I searched the archive with nothing close)

Now when I step on the brake, the dashboard and radio courtesy lights come on. Also the outside parking lights too. Also when the door is open and the brake is pressed, the door buzzer rings. When the left turn signal is used, all four parking lights flash dimly and the dash lights too.

Here's what is OK: All the exterior lights are working, no burned out bulbs, system works fine when headlights are on. Flasher works. Not a single blown fuse in either the cabin fuse panel or under the hood panel. The brake relay is OK, swapped with A/C relay to test. With engine running and accessories on it puts out 14.5 volts. No codes on OBDII.

Sorry for long post - what a bizzare one, huh? Any suggestions? I feel like a BOOB!
Tom

do you have a trailer harness?

If so yank it.

also, yank the ABS fuse and see what happens.

Yeap - yank that trailer harness.

I had one go bad 3yrs ago, had NO lights, period! No dash, no parking, no blinkers, you name it, not a one - and, worst of all, the trailer harness caused that short on an Arizona highway in pitch darkness doing 65mph.

Nothing's more thrilling then playing with wires and fuses over coffee in a truck stop at 2 in the morning :cwm27:

wow, that sounds like fun :disappoin

my heart would have been pounding and i would have been talking to myself alot..you know, like when you try to figure stuff out

Darn, you guys are good. It WAS the trailer harness causing the problem. After work in the parking lot today I disconnected the harness behind the rear bumper. It was one of those HOPPY brand t-connectors. Problem now gone. Many thanks to you- I wouldn't have thought that I boogered it up by working up front. :worshippy

What is involved in removing the trailering wire harness?

Marc

my heart would have been pounding and i would have been talking to myself alot..you know, like when you try to figure stuff out

TRUST me, there was a LOT of that :sly:! But I wouldn't call it "talking" :grinno:

What is involved in removing the trailering wire harness?

Marc

On my vehicle it was as simple as separating the connection about a foot behind the bumper. But this also meant laying down on my back in four inches of fresh snow, while salt and sand fell in my eyes. But it was worth it, my bizarre electrical problem went away. Now I'll be looking for another harness to replace the one that was on there.

On my vehicle it was as simple as separating the connection about a foot behind the bumper. But this also meant laying down on my back in four inches of fresh snow, while salt and sand fell in my eyes. But it was worth it, my bizarre electrical problem went away. Now I'll be looking for another harness to replace the one that was on there.


thanks, I need to look into removing mine.

thanks, I need to look into removing mine.

Yours might be different depending on what type they used. On '98-99 Isuzu put a plug for trailer wiring near the jack. I have a Hoppy brand harness that plugs into that, very easy to add remove that way. The previous owners of mine used a universal one though and tapped into the tail light wires. I removed all that to add the Hoppy one.

Open the compartment where the jack is and look inside to the left of the jack. If they used the factory wiring then there will be a white plug with 6 wires which go down through the body. If not then someone used a universal type which might be tapped into the tail light wiring, in which case there could be a number of way they did it.