Jrhart

Member
Good Morning,

I wonder if anyone could help with this.

About 3 x weeks ago the Defender TD5 packed up. My local garage diagnosed 'topline switch failure' I purchased a new ECU from a main dealer. I fitted it and then the garage reprogrammed the injectors and the immobiliser and it fired up fine. I had an EGR valve bypass kit that they fitted for me.

When the vehicle is cold and the key is at position 2 the temp gauge reads 3/4. when you start up and drive off the gauge starts falling and eventually ends up in the blue but the engine is running fine. Cab heater works fine.

any ideas.

regards

Jonathon.
 
Sounds like you have a Discovery ECU rather than a Defender one as I'm pretty sure I read the temp gauge works opposite between the two. May be wrong though.
Has it ever worked properly since fitting the new ECU?
 
Hi Shifty.

No it has never worked correctly since fitting he new ECU. Is there anything I can do about it or do you think i should go back to the main dealer who supplied the ECU. It makes sense as the local garage asked if it was a Disco 2 one because of the serial number in it. All i did when i ordered it was give the garage the registration number of the vehicle.

regards

Jonathon
 
I'd take the the ECU back sharpish! Whats the part number you have? whats the model of the defender you have
 
If its never worked I'd go back and ask them to sort it.
Or live with it if you dont want the aggro.
Engine will run fine.
You could get an aftermarket gauge and sender.
 
HI.

The defender is a 1999 90 Heritage Le . The part number is NNN500020 there is another number on the box it came in A0849792

thanks

Jonathon.
 
HI.

The defender is a 1999 90 Heritage Le . The part number is NNN500020 there is another number on the box it came in A0849792

thanks

Jonathon.

yes that's one of those ECU's which work for both D2 and Defender just that it's that gauge problem cos the fender's instrument pack is different when it comes about the engine temp. gauge management.... you can try to access the system with a nanocom or similar maybe you can modify some setting there cvos that's what it's stated in the nanocom-Td5 ECU diagnostic capabilities file:
ยท Temperature Gauge: The TD5 ECU has been designed to work with a wide range of
possible fitments and options. Many of the input sensors and output controls can be
omitted giving many vehicle option, model or market variants. This value indicates if this
TD5 ECU has its temperature gauge driving function enabled or not.
 

Similar threads