205 on fire!

Hi,

I have a 205 CJ (1.4TU3M). Have recently had problems with the
immobiliser. The fitter came and bridged it and tried jump starting....
it started but then stopped and no power whatsoever.

We put jump leads on it, but the jump leads caught fire!! The positive
terminal of the battery was red hot (not from the fire though)

The problem I was told is a bad earth.

My question is how do I go about solving this?

The battery is a swap from my CTI so I don't believe the battery is
knackered. I've recently replaced the starter motor but since it did
start when we jump started it I don't believe that's still the problem.
The terminals to the starter are of course different shapes so I don't
believe I've put them on wrong!!

The other recent posting (a diesel 205) mentions the earth straps from
the engine to the body but I'm not sure where those are.

This is perhaps a bit of a newbie question but how does one actually
test for bad earths? I believe I need to invest in a multimeter which
I'm happy to do but what then??!!!

I also have a volt tester probe.

My poor "max" has been off the road for a while and I'm under pressure
to sell the CTI so any help would be appreciated or I fear I may soon
be 205-less!!!!

Many thanks,

John

 

I can't see the logic in that. Usually a "bad earth" means high resistance
in an earth wire/bonding so that would mean low current and less heat. It
looks more like a short circuit from positive down to earth. I would suspect
the work done to bridge the immobiliser. Of course if you tried and tried to
start the car then that could make the terminals hot but only if they
weren't tight in the first place.

Yes you will need a multimeter but they aren't expensive. Maplin often do
digital ones for a couple of pounds. What I would do is remove the battery
if you haven't already done so and start measuring between the various
wiring points from the battery down the circuit to the starter motor. I
reckon that you will find a short somewhere. Obviously when you do find the
short you'll need to isolate that part of the circuit to find whether the
short is upstream or downstream of that point. This isn't a terribly good
description but I'm sure you get my drift.

A bad earth will mean high resistance between a part that should be earthed
and earth. You could check for this by putting a jumplead from the cylinder
block to battery negative. If the engine starts then you have a bad earth
and you'll need to find the earthing straps and take them off and clean the
connections etc.