Headlamp Relays

[Jon280]

Well I think that a bit of water ingress yesterday while having the car washed has damaged a relay or two for my headlamps. They will pop up sometimes, but not all the time, and then if they do, will randomly go down again (both at the same time, no winking from them). If I put on full beam, the pods pop up and full beam comes on regardless of the lights already being on or off.

So, are the relays anything special, as I want to get them sorted tomorrow hopefully so I can get to the Ace meet, but don't want to do it without headlights being available! Will something like this from Maplin do the job ( http://www.maplin.co.uk/40a-relay-for-automotive-a...). I know there are probably cheaper sources online, but I want a shop I can get to tomorrow to get them!

Cheers!

[Jack Valiant]

Would b surprised if its the relays especially if the motors are / have been working Jon.

First check the simple stuff are the fuses ok, as its been washed I would get under each front wing and pull apart all the connectors and dry / clean the connectors a small pin file or screw driver will do. Do both sides and check for effect. If no joy then with the lights in the dipped position gently tap each light motor relay with a screw driver and check for effect. If you get intermittent operation with the taps then replace the relays. Finally if no operation then check the diode or diodes for operation let me know if you need help with it?

Good luck and let us know what the outcome is!

Chris

[RCK974X]

A direct answer - NO the relays are NOT anything special. There is one relay which is a 'changeover' type which feeds 12 volts to an 'up' or a 'down' wire , these two wires go via the motor switch boxes, then there is one plain relay for each motor to run it. The motors always run in the same direction. (and then diodes in a few places)

What you describe sounds like it's probably a dodgy connection somewhere, and my favourite cry on TVR boards - "Check your Earth returns !!" as a dodgy earth can cause a big list of truly weird symptoms.

I remade the earths on mine and cleaned all connectors, and instantly the pods went up and down faster, headlamps brighter, horns louder, etc. etc.

The water ingress suggestion says to me that a faulty earth is high on list, but check ALL the connections (even fuse holders !) to be sure.

Also could be dodgy relay, I agree, diodes tend to either fail or work, so less likely, and I would check all connections and earths first....

Edited by RCK974X on Tuesday 18th June 20:32

[jon haines]

I had similar problem once when I power hosed front end fo get rid of bugs. Water got into the connectors underneath and lights did as you said so disconnected lights dried everything off and worked fine.relays are same as TR7.

[Jon280]

Hopefully will have a chance to investigate a bit tomorrow. I initially suspected the relays, as yesterday when I had it washed yesterday, when I got in to move the car there was some water dripping down in the area of the relays in the passenger foot-well, and on mine, the headlamp control relays are at he top of the board and in the direct line of fire of said water.

May be worth adding, it was not just the pods not popping up, but the dash lights were also not coming on, until the pods did then lift, at which point they cam on again, and went off at the same time the pods dropped of their own accord.

[Jon280]

Problem solved.

Checked the headlight connectors, diode and swapped relays around. No change and no headlights.

As main beam would work, went to check the headlight switch, and the highly technical method of wiggling the wires under the dash made the lights pop up and down.

Have given that connector a clean and all now seems well!