Possible ground short???

[c.douch]

Hi all,

I've got a few minor issues and was wondering if they could be related:

1. The blower doesn't work at any speed. I've checked the connections with a mulitmeter, and whist the live connector seems fine, the ground doesn't appear to be connected to ground.

2. The fuel pump fuse (fuse 1) tends to blow whenever i try a hot start.

3. I fitted a new stereo (totally non-invasive and hidden behind the passenger seat as i don't want to take away any originality), however the sound keeps cutting out after a few minutes. I had assumed it was the stereo, but am now wondering if the speaker impedance is being effected somehow via the ground connection.

I thought about the following fixes:

1. just connect the ground of the blower motor to another ground connection (there seems to be another one on the blower casing, although i'm not sure what its for).

2. Get the engine hot the unplug the fuel pump, then see if it'll hot start (hopefully it should just catch on whats in already in the system before cutting out). Which will tell me if it's a faulty pump.

3. Test the stereo in another car, if it works okay, ebay it and buy a battery powered hifi.

However, I'm now beginning to wonder if they are all part of a larger, or related issue. A short somewhere in the system.

I'd love to have you're thoughts on the matter, before I start tearing out any wires.

Many thanks

Chris

[Rissy]

You've got a complicated set of issues there. All weird in nature i think. weirdness normally indicates grounding issues, as you've suggested.

There's no quick fix i'm afraid (i'm speaking as a person who's also got a troublesome grounding issue on his own car).

It's gonna take some perseverance and hunting round the car with a multi-meter.

Have you got a good copy of the vehicle wiring diagram? This is a very good place to start the process of ticking off and checking what you have (good or bad).

There's also some drawings some one has done which illustrates all the grounding points for the loom on the vehicle. Do you have these?

When you look at these pieces of information, you'll see the Fuse #1 connects to the RPM relay. Perhaps this has gone faulty, giving a direct short, but only when something has warmed up (expanded due to heat?) Perhaps you could try changing out the RPM relay for a new one? Also, the idle speed regulator circuit is fed via this fuse, as is the vacuum solenoid and the engine ECU. You could investigate these areas too.

The blower motor requires a supply coming through from Fuse #10 (i think you've identified that already). The other common part to all of the speed settings is the ground connection at the motor itself. Have you checked that?

Electrical issues are difficult for anyone not near the car to help with. It's going to be a bit of a slow (and painful) process unless you have a stroke of luck.

Have you thought about Ebaying the car? ;-)

[Chris Williams]

Other than what Chris has suggested above (all very good and valid points) I would suggest actually checking the grounds that you should have. Just because they look ok does not mean that they are. It's not uncommon for there to be 'odd' electrical problems with these cars. If it were me I would start by disconnecting any thing you have done (Radio) and then start again with your checks.
Chris

[JohnC]

Whilst my lack of anything approaching technical ability is well known to my fellow owners.....



Grounding issues were something I did experience. Many of my weird problems with the centre cluster were due to the common ground point on the right of the centre console.

Might be worth a look.