I've got a '97 Disco - it's been a wiring nightmare due to a melted harness.

The vehicle starts fine and idles great (cold start - having issues with hot start conditions, but that's for another day). However, upon shut down, the fuel pump relay(I'm thinking that's the correct one) clicks several times - YWB 10041 C, by the fuse box under the hood.

Other things that are happening: The battery light is dimly lit while the disco is running, and the trailer light that's supposed to blink only once stays on. As a matter of fact - both lights stay on when the vehicle is off as well. I'm not sure, but I also hear a relay clicking under the passenger side dash as well.

Looking for ideas while I test the charging system. Battery is brand new.

Thanks!

 

Sounds like a ground fault... find it in RAVE electrical troubleshooting section, section Y-5 ground E200 may be a good place to start since the light is on always...

just a guess.

 

Thanks, Cosmo. I'll dig in the RAVE and see what I find. Thanks for pointing me to E200. I'll see what I find on Friday...since I'm sure if spending tomorrow under the dash in the disco will be looked on unfavorably.

 

Good luck with it. I would check all the grounds. Did the entire harness melt? Was the actual cause determined and corrected?

I had to completely redo my starter and battery ground connections to the frame due to excessive corrosion. I repositioned them to the side of the frame, abraded it down to bare metal with a large deburring bit from a Dremel set and used self-drilling bolts to terminate them to the frame.

 

That's the plan - looking at all ground connections and cleaning them up.

It wasn't the entire harness, but pretty much everything having to do the with front lights/alarm was one big melted mess. Also affected was part of the engine management, including some of the sensors and IACV. I bought it in this condition (knowing it had wacky electrical issues), but was surprised at the extent. The main damage to the harness was on the left fender, by the airbox - they had 'fixed' it by relaying the lights off the other other side, which created a whole set of other issues...

I suspect I'll be spending some time with a drill and the dremel as well... I'm sure I've missed something.

 

Make sure your belt is routed correctly first, it can look correct but actually be on wrong and not charge the battery correctly and set off the battery light on the dash.

As for the hot start issue, bad fuel temp sensor.

I would imagine that the fuel pump relay will stay energized for a short time after shut down.

 

Well, a little more info:

The belt is routed correctly, comparing it to the example posted on this site.

The indicator lights that stay illuminated on the dash are the trailer, SRS, oil, and battery. When the disco is running all are off except for the trailer light. I'm going through the grounds now, so the fun's just beginning.

Wow, the fuel temp sensor is a pricey one. In my experience in troubleshooting sensors on Audis and BMWs, the manuals provided me the resistance measurements of the sensors to see if they're in range before I replaced them. Anyone have a source for those values if they're available?

Thanks for the pointers!

 

As far as cleaning the existing grounds, you may be just as well off to totally reposition the grounds to a new location near the current one. I did this with both my battery ground cable and starter ground cable connections.

I drilled a starter hole directly into the frame after abrading a spot down to bare metal using a dremel deburring tool to remove the undercoating from the frame. I then attachd the new lugs directly to the frame using self-drilling bolts in a power drill. Works great.

 

full range of temp / values... 23k-ohm @ -22*F all the way down to 290 ohm @ 176*F

Ohm's will drop in value as the temp rises as you can see from above figures...

Here is some handy info you may not have - http://www.docstoc.com/docs/19519919...nt-Systemsbook

 

Cosmo - brilliant! Thanks! The link is exactly what I was looking for. Very much appreciated. I'll update later today on what I find, both with the sensors and the grounds.