31 replies to this topic

[zimmer]

Hi, hoping someone has had a similar situation Suddenly noticed that my sidelights and headlights don't switch on, front and rear. The indicators and hazards work. The main beam flashes from the steering column ok. The led light in the switches don't come on First step was to check the switches - I've exchanged for fog light switches, no change I've checked all the fuses, replaced all headlight related fuses with fresh ones. No loose wires in back of fuse box I've had the dash off, cleaned and refitted the 3 relays near the light switches Seemingly randomly after doing this the abs light on the dash has now lit. The wires from the hubs are fine. The lights were fine til the other day, just passed its MOT. Can't think of any reason they would suddenly stop working. My next plan was rear wheelarch out and clean the relays behind the coolant tank Any help greatly appreciated!

[james_ly]

Headlight relays are in the front by the fuse box. I'd swap it with the horn relay for now.

[zimmer]

Thanks James. The horn relay is working. I've swapped this in for the dipped and main beams, no joy. Just taken it out for a run. Speedo doesn't work, now the hazards don't work, and the engine died at the traffic lights (runs fine but won't idle). Guessing this could be loom of doom? Speedo is the nearside rear abs feed right?

[smiley]

With so much going wrong, could be an earth wire.

 

[zimmer]

Hmm thanks smiley. Sounds like a day finding and cleaning earth connections is needed

[zimmer]

Ok so today I've tried switching all the grey relays with a known working one - under the dash, next to fuse box, in the boot I've disconnected and cleaned the loom of doom I've removed the headlights - one of the spade connectors was loose so tightened it up I've disconnected the lights one by one to see if the others work with one disconnected I've cleaned the battery negative terminal and earth connector there The front chassis earth looks clean and corrosion free I found one of the engine earths and cleaned it up although it looked fine I can't find the rear chassis earth or engine earth number 2 Interestingly I found that the hazard lights fuse had blown. After replacing this the abs light magically went out - weird Any ideas where to go next? Does anyone know an auto electrician in Leeds area??

[Johnboyhgt]

Relay positions here. its relay k20 you should concentrate on which is the one behind the switch pack under the dash.

 

Happy to take a look for you - I'm in York.

 

http://www.vx220.org..._151_139861.jpg

[fezzasus]

Unbolt the fuse box and relay boxes (above the front wheel arch) and check the condition of all of the wires going into each box. These tend to corrode there. Don't limit your testing to just ground wires as some cars use switched ground and a common 12v

[Pidgeon]

Link wire under the fuse box, there's a single wire running diagonally that corrodes away - do a search

[Pidgeon]

http://www.vx220.org...-or-headlights/

[zimmer]

Thanks Pidgeon - I already saw that thread and hoped that would be the problem but the wires to fuse box and relays all look fine, none loose or snapped.

Theres minimal resistance from the headlight and sidelight fuses to the negative battery terminal with my multimeter so I think that the earth side of the wiring should be OK.

Johnboy - I've tried switching K20 for the horn relay which I can tell is working. The relays themselves seem to be OK. Maybe a connection to the relay? Not sure how to test this yet...

 

I've fixed the abs issue - this was a loose connection at the fuse box - wiggling the abs fuse caused the module to click and that seems to have resolved with some contact cleaner.

 

So I'm still left with no sidelights or headlights. The switches are getting power as the symbols illuminate, but they don't seem to do anything, the leds also don't light. I'm sure its not the switch thats broken as Ive swapped them all around

 

Fezzasus, I'm not sure how to go about testing the live side of the circuit as I'm pretty much an electrical numpty (though have learned a lot over the last few days!) so might be time to call in the auto electrician I think.....

[Nev]

Try disassembling a switch and short the contacts that it fits into to see if the lights come on, in order to check if it's the switches at fault.

 

[Johnboyhgt]

Simple test - ignition on and relay k20 in your hand press the sidelamp switch - does the relay click in your hand.

 

If so Remove relay k20 and test with the lights on that you have power +12v at pin 30 of the relay (unplug relay and look on bottom of it to see which connector that is)

 

(Ie black of multimeter to an earth point and red to the 30 of relay multimeter on 20v (or just V DC if autoranging)

[Johnboyhgt]

Try disassembling a switch and short the contacts that it fits into to see if the lights come on, in order to check if it's the switches at fault.

 

 

Couldn't you sleep Nev ??       5.44 am

[zimmer]

Ok so k20 relay doesn't click. It also has no voltage at pin 30. I know I'm doing it right as the front fog relay next to it also doesn't click but I do have 12v at pin 30 on that. For what it's worth I have 12v at all the fuses except fuses 16 and 17 At the switch, I get 12v from the connector top left as you look at them, but no voltage from any other connectors I tried shorting the 2 connectors at 3 o clock and bottom right and it didn't do anything. I'm not sure if these are the right 2 to connect though. Tearing my hair out with this - appreciate all of your help!

[vocky]

FB19 (10Amp fuse) supplies power to the sidelight switch (S4), which then supplies power to the relay K20 - pin 87A, then via fuses FB16 and FB17 to the sidelights

 

Relay K19 powers the low beam, 12v comes from FB14. Headlight switch S2 powers the relay coil via pin 85 (other side of coil goes to chassis 0v)

 

FB14 and FB19 come direct from the battery, so should have 12v on one side of the fuse holder (with fuse removed)

Edited by vocky, 08 June 2016 - 05:45 PM.

[zimmer]

If it helps at all I get about 1.5v at pin 87a on K20 when I push the sidelight switch but nothing when the switch is off

[vocky]

circuit diagram

 

http://www.speedster...am/Low beam.pdf

[vocky]

you need to check the power at the sidelight switch pins 2 + 3

 

3 = 12v

 

2 = switched 12v

[zimmer]

I have 10.8v on one side of both those fuses. 3v at pin 3, nothing at pin 2