Technical Panda 2008 P0520 the car won't start and makes no sound when turning the key

[Malisz]

Thats 3 different people suggesting the correct action

What method did you employ with your friend to rule out the Main Earth Cable


( I have yet to see one of mine fail.. so am keen to learn of potential pitfalls)

It was actually a proper mechanic, I didn't really know what to look for myself.

Im a total car noob, so didn't know what to lookout for, but I think what I did wrong was that I was trying to ground the wrong part(maybe?).

The mechanic found the faulty wire, it was rusty and apparently had a screw running through it which weakened it and that combo caused it to fail.

 

[Malisz]

Ah and just to add one more thing. It would have been much easier, possibly I would be able to figure it out myself, but I couldn;t find my multimeter.

 

[koalar]

@Malisz
Thats 3 different people suggesting the correct action.. test and replace the Earth circuit

What method did you employ with your friend to rule out the Main Earth Cable ?


( I have yet to see one of mine fail.. so am keen to learn of potential pitfalls)

the best way is a voltage drop

scrape a bit of the battery terminal to shiny metal green scouring pad works well

you need the same on the gearbox or engine. A file works well here

multi meter on volts. A lead on each cleaned spot and crank the engine. Anything under half a volt is fine

Jump lead test is fine but you have to make good contact.. I use the gearbox selector cable bracket also you need leads that can cope with the high amperage, I bought a set many years ago that wouldn't jump start an old Volvo with it headlights always on

 

[koalar]

@Malisz
Thats 3 different people suggesting the correct action.. test and replace the Earth circuit

What method did you employ with your friend to rule out the Main Earth Cable ?


( I have yet to see one of mine fail.. so am keen to learn of potential pitfalls)

here's how i would check power and ground on a starter motor, not so easy on the fire engine being covered by a plastic cover

earth still works the same and can be done from the top

an incandescent test light is so useful. They allow enough current through them to activate a relays but not enough to fry a ECU, didn't carry one for years but is now part of my carry repair kit again

 

[The Panda Nut]

What method did you employ with your friend to rule out the Main Earth Cable ?
( I have yet to see one of mine fail.. so am keen to learn of potential pitfalls)

When my battery failed I tired a jump lead from the battery bayyery negative termibal to the gearbox. it made no difference, I took this to mean the earth was not involved in my woes. I did remove it inspectthe earth, and cleanedand greased it before repalcing while the battery was out of the car. It was fine with no deterioration and both ground points were also clean. If the earth was faulty the jumplead should act as a temporary replacement and fix the non starting while connected.