Kent_Hughes

Hi Guys,

My Load reduction relay went (ie. wipers, blinkers etc.). I got a new one, and replaced the Relay. One of the RElay terminals was visibly burnt, and the casing of the relay next to it had a scorch mark on it too..

more worryingly, the 75x terminal was burn too, and it looks like the black/yellow cable taht runs from 75X also burnt a little (it looks like the plastic cover has shrunk).

I replaced the relay and everything started working correctly.. for around 10 minutes.. then everything stopped. Pulled everything apart again, pulled the relay, looks ok.. put it all back again.. Tried the car again, everything works.. 5-10 minutes later relay has stopped again.

I eventually pulled one of the Air con relays (#25 i think) and since then everything has worked (other than the A/C)

Has anybody got any ideas were i should be looking? is the 75X wire fused? and where how does the 75x cable relate to the a/c?

any help would be appreciated.. most load relays seem to be resolved with a new relay.. but mine keeps having an issue.

Kent

ModifiedA4

it cuts power to everything that is "on" when the engine is cranked.

the more stuff that is "on" when the car is started the larger the load through the relay, and after too much load there would be arcing as the contacts close. sometimes the arcing welds the contact closed and the coil overheats and the relay melts.

-have you wired any other crap into the car that is "on" when the car is started? stereo? radar detector? etc...

-if not, then something else is incorrectly "on" causing too much load. since you mention the A/C, im assuming the A/C clutch is incorrectly engaging, or you routinely have the A/C "on" when starting the car.

-make sure you turn everything "off" before you shut the car down. I make sure to turn the radio off, A/C etc. the problem isnt the load reduction relay, its the load.

-another thing that can cause a ton of load is a short circuit. though I suspect that a fuse would blow, preventing the load reduction relay from taking the brunt.

audinutt

sounds like your a/c blower motor might be the cause

Kent_Hughes

is there any way to test this? after i replaced the relay, the A/C, blinkers etc. all worked ok.. had air coming through the vents etc.. (so i guess it is a possitive that the blower motor hasn't seazed or anything)

it was only when i was actually driving the car, with A/C on (from memory, fan was definately on) and i turned the blinkers on that the relay blew.

Is there a fuse i can pull to disable A/C but leave the fan operational for testing?

Kent_Hughes

that is a good explenation thanks.. i would have presumed that there are fuses before they are summed into the relay though? so if there was a large load being presented on one of the circuits.. wouldn't it trip a fuse?

I have upgraded to an RNS-E using an adaptor into the stock harness, and there is nothing else on the 75x load that i am aware of)

most of the time i do not have A/C on. so it is hardly ever on when i start the car, The relay seemed to work ok while i tested it in the garage. It was only when i was driving that it blew (first time i pulled the relay out and put it back in, and that seemed to "reset" it. Second time i did the same and pulled one of the A/C fuses)

so maybe you are right on the A/C kicking in randomly and causing the load. Other than the blower motor, and a switch for the A/C compressor, is there much else electrically in the A/C system?