Thread: Spotlights wont dip off with high beams

Hi dhumphri, if you are using just one relay to power the driving lights, try tapping it when the driving lights stay on. If the lights turn off, it’s a pretty safe bet that the relay is the problem.

If you are using more that one relay, then the problem is more than likely wiring.

Also, depending on whether you headlights are powered by relays, it could be a dicky dimmer Sw but that would be a last line of investigation.

Cheers.

Go the relay, most likely underatted for the job and now suffering contact sticking as they are welding themselves together with the current.

Could you have anything else go wrong with that truck

I have had two relays fail this way by the points melting together. Both were rated at around three times the current draw!
John

[quote=seqfisho]Go the relay, most likely underatted for the job and now suffering contact sticking as they are welding themselves together with the current.

I agree

If you switch all lights off then on do spotties still stay on or do they reset .

Thanks boys - will track down the relay tomorrow and replace.
Seqfisho I am just waiting for the next thing to break - glad I did not buy one with a crap service history.

On the up side Bruce Davis replaced the ECU with a different one today and the truck is now on song - touch wood.

Hopefully now I can start doing some of the mods I wanted to do instead of just break/fix stuff.

Autotechnica seats here I come...

what brand relays are you running....?

mmmmmmmmm .... interesting problem
had a similar one myself once with the wife's verada.
(Twin factory headlights - Hi/Lo outer, Hi inner)

I was running 2 x H4 90/130's + 2 x H1? 100's and they kept on blowing the factory relay at the most in-opportune times
(Darkness + Darkness = 100kmh darkies )

I checked out all the potential problems as listed above, and was all OK.

got sick of it and removed the whole lot (Still haven't solved it .......... gave up......... back to 60/55's + 100's)

Was particularly interested in project 2A and on closer inspection realised that it's similar to what I had done about 12 months ago, ( 3 x Double relays - Hi/Lo Right, Hi/Hi inner, Hi/Lo Left)

Here's what my theory was ...... (ready Mr Drivesafe )

Power was feeding back through the headlight common and keeping the relay coil charged so as not to release the contact when the lights were dipped. Normal operation resumed by switching the headlights off and back on. (never got out on the road with it like that)
BTW... from memory the light circuits are Neg switched

Input appreciated .... and I might get the project out again

Hi sschmez, yours is a common problem that most people strike, when attempting to work on headlight wiring.

You are literally wiring into the headlight loom, in series.

When the kit is available, I have now added a small 3 pin plug which guaranties that the connection to the headlight loom is in parallel, because the plug simply fits into the headlight socket.

This plug set up not only simplifies the installation, it greatly shortens the install time because it removes the need to have to determine whether the vehicle has positive or negative headlights and also means you don’t need a multi meter to carryout the installation.

Cheers and better luck with your next try.