Sambarhunter

New Member
Have you had key FOB Issues and can't work out why?
This is a long post so bear with me, it may just solve your problems.
Ok, so I've recently had key fob issues where initially the car wouldn't start and after three turns of they key it would fire. Usually very intermittent and then one day, absolutely nothing!
Cut a long story short, it took me a long time to establish what the problem was. I pulled the internal fuse box out, sperated the cases, and noticed there was sign or water on two tracks. Now as the internal fusebox has the IDM PCB for the BCU, this can cause all sorts of issues with the BCU controlled outputs. Luckily for me it wasn't the fusebox even tho I did replace it to be sure.
I also got a known working BCU and key that came from a donor car, but it made no difference, still no start!
After a few months of trying to program with the Nanocom and constantly noticing that a key would not detect. I came to the conclusion this has to be an RF receiver problem to the BCU, correct? Id also replaced RF units aswell, which did squat
After realizing that the BCU was not getting the RF signal I then traced out the three cables off the RF 315mHz unit back to the BCU, one being antenna cable the other two being positive and negative I assume.
To my surprise, after removing the passenger kick panel, the cluster of loom plugs had corrosion inside the terminals, which was not allowing either signal or voltage to travel back to the BCU
I'm yet to trace the water ingress cause but, it could be from the skuttle panel under the windscreen or off the roof/gutters. It seems like it wicks down the cables to the lowest point being the plugs.
I sprayed the terminals and carefully pulled the terminal plugs apart and scratched up the pins with a flattened out metal staple to remove the corrosion.
Straight away the Nanocom detected a key and I then went ahead and programmed two keys with ease.
The car then started immediately and locks and unlocks like it never has
I'm actually thinking the water is
Wicking down the cable from the heated windscreen plugs that aren't in use, just like the injector loom as a culprit.
If you do find the a BCU is in need of repair use Rick from Callrova in the UK.
Without slagging off other similar businesses in the UK he is the only guy to talk to.
If I can help you with what I found , I'm happy to chat.
Please see pic for reference below.
inbound7293184187133904526.jpg
 
Have you had key FOB Issues and can't work out why?
This is a long post so bear with me, it may just solve your problems.
Ok, so I've recently had key fob issues where initially the car wouldn't start and after three turns of they key it would fire. Usually very intermittent and then one day, absolutely nothing!
Cut a long story short, it took me a long time to establish what the problem was. I pulled the internal fuse box out, sperated the cases, and noticed there was sign or water on two tracks. Now as the internal fusebox has the IDM PCB for the BCU, this can cause all sorts of issues with the BCU controlled outputs. Luckily for me it wasn't the fusebox even tho I did replace it to be sure.
I also got a known working BCU and key that came from a donor car, but it made no difference, still no start!
After a few months of trying to program with the Nanocom and constantly noticing that a key would not detect. I came to the conclusion this has to be an RF receiver problem to the BCU, correct? Id also replaced RF units aswell, which did squat
After realizing that the BCU was not getting the RF signal I then traced out the three cables off the RF 315mHz unit back to the BCU, one being antenna cable the other two being positive and negative I assume.
To my surprise, after removing the passenger kick panel, the cluster of loom plugs had corrosion inside the terminals, which was not allowing either signal or voltage to travel back to the BCU
I'm yet to trace the water ingress cause but, it could be from the skuttle panel under the windscreen or off the roof/gutters. It seems like it wicks down the cables to the lowest point being the plugs.
I sprayed the terminals and carefully pulled the terminal plugs apart and scratched up the pins with a flattened out metal staple to remove the corrosion.
Straight away the Nanocom detected a key and I then went ahead and programmed two keys with ease.
The car then started immediately and locks and unlocks like it never has
I'm actually thinking the water is
Wicking down the cable from the heated windscreen plugs that aren't in use, just like the injector loom as a culprit.
If you do find the a BCU is in need of repair use Rick from Callrova in the UK.
Without slagging off other similar businesses in the UK he is the only guy to talk to.
If I can help you with what I found , I'm happy to chat.
Please see pic for reference below.View attachment 264543
thanks for this! I am sure everyone with a TD5 will be interested in this.
Including me!!!:):):)
 
From the top down your ingress could from any of the below.
Sunroof
Roof Bars
Gutters
Windscreen
Oval grommet in passenger footwell for Loom.
 

Similar threads