Thread: PUMA Electrical Problems after some rear Chassis welding...

- any logged fault codes?
- have the battery terminals been checked and made good?

Might be long shot but the handbrake light might be a clue
That light is earthed directly via the handbrake switch to the floor pan

A mates 110 Puma tried to burn itself to the ground via dead shorting that switch!
Quick use of fire extinguisher and killing the main fuseable link saved the day

I could foresee that high resistance battery lead connection may give a funky partially earthed signal to the handbrake -



The reason I am looking for the outside possibility is just a few weeks ago I rewelded my headboard - earthed right near the weld (as I’m guessing happened on your mates) and absolutely no problems with my 2009 130
BUT and the big BUT I didn’t disconnect batteries
There is the theory that leaving the batteries connected adds a big capacity between any stray current via the chassis. Disconnecting battery does not disconnect the ECU earth path to the chassis????

Hopefully it is something simple

Being a 2009 - if you have a BAS IID tool handy you could download the code email it to BAS and get their opinion / rewrite on it perhaps?

S

Sorry I forgot mention that there was no codes up when the mechanic put the diagnostic tool on.

I’ve since found out that he had longer brake lines fitted, so the handbrake light coming on might just be low brake fluid or right on the limit...

Doing a bit more research... it was suggested that it could well be the speed sensor as this interacts with both ecu’s...

Originally Posted by Robmacca

Sorry I forgot mention that there was no codes up when the mechanic put the diagnostic tool on.

I’ve since found out that he had longer brake lines fitted, so the handbrake light coming on might just be low brake fluid or right on the limit...

Doing a bit more research... it was suggested that it could well be the speed sensor as this interacts with both ecu’s...

I’m following with interest so appreciate the updates.

Likely...
*The handbrake light flickering will be unrelated as its common on the 2007 on wards model for the handbrake cable to stretch and or fail.
*Ensure the battery terminals are tight and secure.
*The Defender has very very limited code so its not surprising there is nothing showing up.

Bit of an Update....

Spoke to the mate and it appears the flickering handbrake was definitely related to the install of longer brake lines and thus lowering the brake fluid level down to limit. Topped up and looks all good so far

The Main issue: After a bit of research on another overseas forum its pointing more towards a faulty speed transducer. A new transducer has been ordered and will see what the outcome will be...

Originally Posted by Robmacca

Bit of an Update....

Spoke to the mate and it appears the flickering handbrake was definitely related to the install of longer brake lines and thus lowering the brake fluid level down to limit. Topped up and looks all good so far

The Main issue: After a bit of research on another overseas forum its pointing more towards a faulty speed transducer. A new transducer has been ordered and will see what the outcome will be...

Just heard back from the mate... mechanics replaced the speed transducer and the problem is still there.... apparently next item to look at replacing is the instrument ecu...

The mate just got back to me & told me that the mechanics found the plastic gears within the Transfer Case that are used by the transducer to measure your speed - apparently the plastic gears were partially stripped.


The mechanic removed the backing of the Transfer Case to access these plastic gears and replaced them and all is NOW GOOD according to the mate, so in the end not as bad as it was looking, just mainly labour costs to track down problem...


Curious... These plastic gears - if they totally fail totally I wonder what happens to the drivability of the car? Would u still be able to drive it or not??

The guy that has done high level welding for me for many years will not weld on a vehicle unless the owner takes the alternator and batteries out first. People tell him this is no longer necessary. He tells them "take it elsewhere". He has been doing this for 50+ years and won't budge. Sick of being blamed for electrical problems.