Thread: TD5 blowing fuses, help wanted.

Originally Posted by guitarcher

The one located under the fuses.Third from the right. ???

There famously in no headlight relay in the Defender! hence there tendency to burn out HL switches and the general dimness of the HLs. once you have identified your current (no pun intended) issue then I would recommend fitting one.

May not be your answer but fit a Traxide headlight upgrade kit that includes relay.
The 2 fuses blowing could be related or may not be.
I found my issue blowing dash light and tail light fuse. The expensive Narva weather proof plug had slop in the pin and receiver. Result of hollow pins moving and wearing, losing contact and then contacting again. Fixed today.
I also had problems similar to yours and found it was a solder join in the wiring harness had come apart and was arcing and also arcing onto another wire after wearing through. The issue with this is these joins are in the harness at the back drivers side of the car where the trailer wiring is (regardless of whether you have a towbar fitted or not). This join section is where the harness enters the chassis and can be difficult to find.
The other scenario is you may have a wire or more than one worn through. Look for any wear in your harness looms.

Originally Posted by Leyland1980

There famously in no headlight relay in the Defender! .

Thanks for pointing this out to me.

Originally Posted by guitarcher

The one located under the fuses.Third from the right. ???

There is actually a "headlight relay", and it is in the position mentioned. All it does though is switch the headlights off when the ignition is turned off. So yes, Defenders do have headlight relays; just ones that only stop you from draining your battery by leaving the lights on rather than anything useful.

First up, what that fuse 15 does; it is powered directly from the ignition switch and feeds a number of things that need to know when the vehicle is switched on. Some examples: A/C, heater, blower, heated screens, headlights, power windows and instruments. In theory, none of those should work without the fuse. The instruments are not linked through that headlight relay. The relay is switched by a feed from that fuse - and the instruments are powered from that fuse - but they are not really related functionally.

Apart from that, I can't really help - not enough information. I would suggest that the problem may be that the two circuits (fuse 21 and fuse 15) are shorting to each other. That is the only suggestion I can offer.