Headlights go off when switch to high beam!!
#1
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Headlights go off when switch to high beam!!
Pretty disconcerting the first time it happened, which was in a dark canyon at the time. Did a search, but only found one thread close and that was for a FC that was stuck in high beam and wouldn't switch out.
To diagnose and try to correct I:
1. Replaced the dash flash switch, no change.
2. Replaced the headlight relay (which the shop manual gives every indication should be the cause), no change.
Anyone heard this one before?
Any suggestions?
To diagnose and try to correct I:
1. Replaced the dash flash switch, no change.
2. Replaced the headlight relay (which the shop manual gives every indication should be the cause), no change.
Anyone heard this one before?
Any suggestions?
#4
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The fact the low beams work fine but the high beams don't proves that the fuses, headlight switch, headlight relay and grounds are all fine. The problem will either be the bulbs or the dimmer relay.
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High beam's are rarely used, so it would be really odd if the high beams in both headlights are buned out where low beams are working fine.
This is a real stumper.
This is a real stumper.
#7
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I'll switch out the headlights and report back. Still skeptical, but more odd things have happened...................................
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#10
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Originally Posted by HOZZMANRX7
High beam's are rarely used, so it would be really odd if the high beams in both headlights are buned out where low beams are working fine.
I take back what I said above too. It can't be the dimmer relay because it's obviously changing from low to high. That just leaves the bulbs.
#11
yes,thats me \/
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is it possible that the high beam circuit is shorted out? so when you turn it to highbeams the power gets diverted and never makes it to the headlights. get a volt meter and see if the highbeam circuit at the bulb is reaching 12 volts. if it is not, then tap into the wire and work your way back in the circuit to see if you can get 12 volts anywhere. if you do, there is a short between where you have power and where you dont. if you have a very low reading it might be short to voltage (feeding into another circuit) and it is not enough power to light the bulb. check the obvious first however, like bulbs,fuses, etc.
#12
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I take back my question, headlight relay and dimmer relay are clearly different relays.
Further, on checking, the highbeam indicator comes on even though the high beams don't. Since the indicator sources from the same power circuit as the lights themselves, clearly the circuit is getting power. So, strange as it seems, it has to be the headlights themselves.
I'll swap out the light units tomorrow and report.
One high beam maybe, but both at the same time?
Weird!!
Further, on checking, the highbeam indicator comes on even though the high beams don't. Since the indicator sources from the same power circuit as the lights themselves, clearly the circuit is getting power. So, strange as it seems, it has to be the headlights themselves.
I'll swap out the light units tomorrow and report.
One high beam maybe, but both at the same time?
Weird!!
#13
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Originally Posted by cdaleracer669
is it possible that the high beam circuit is shorted out?
Instead of just guessing, look at the wiring diagram to see how the system works. If you understand that then you'll see how none of the suggested failures could leave the low beams working as described.
Originally Posted by HOZZMANRX7
Further, on checking, the highbeam indicator comes on even though the high beams don't. Since the indicator sources from the same power circuit as the lights themselves, clearly the circuit is getting power.
I'll swap out the light units tomorrow and report.
One high beam maybe, but both at the same time?
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So the fact that my high beams work sometimes and dont others, and sometimes the lights will go out completly when i switch between the two, say that its the relay?
I have to put my manuel switch on so they alway stay up and then flick the lights on and off again till they come on.
I have to put my manuel switch on so they alway stay up and then flick the lights on and off again till they come on.
#18
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I had a bad swith and that was the problem. You could select high beam and be driving along and then they'd go low beam all by themselves. I'm talking the switch on the cluster, the one you flip with your finger to go to high/low beam.
Could be another thing all together.
Could be another thing all together.
#19
pistons?!
I know they had a bad time soldering connections in these cars...lots of brittle stuff breaking off and what not...something could have been knocked loose...
#20
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Originally Posted by NZ_87_TURBO
So the fact that my high beams work sometimes and dont others, and sometimes the lights will go out completly when i switch between the two, say that its the relay?
I have to put my manuel switch on so they alway stay up and then flick the lights on and off again till they come on.
I have to put my manuel switch on so they alway stay up and then flick the lights on and off again till they come on.
Originally Posted by jgrts20
The Headlight relay is the same as the dimmer relay...
#21
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[QUOTE=NZConvertible]That definitely sounds like a bad headlight switch /QUOTE]
gutted. thats like my 3rd switch. I have my realy stuffed down under the other ones coz it goes sometimes and dosnt other. and it its sitting upright ( how its supposed to ) it dosnt go at all
must be the relay.
Do you know the part number for the headlight switch wiring harness?
gutted. thats like my 3rd switch. I have my realy stuffed down under the other ones coz it goes sometimes and dosnt other. and it its sitting upright ( how its supposed to ) it dosnt go at all
must be the relay.
Do you know the part number for the headlight switch wiring harness?
#22
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Nope sorry, I only have US parts catalogues The LHD and RHD harnesses will most likely be different.
I might be wrong about the switch. The relays are easy to check, see the FSM Body Electrical chapter page 14-46. If either are dodgy they can be replaced with generic 30A automotive relays (as long as you weatherproof them).
I might be wrong about the switch. The relays are easy to check, see the FSM Body Electrical chapter page 14-46. If either are dodgy they can be replaced with generic 30A automotive relays (as long as you weatherproof them).
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I have a similar problem at the moment. Suspect it is the hi-lo beam switch. Low beams work fine, but engage hi beams and no lights at all! Pullung the indicator stalk back towards me and the high beams come on, push it forward and they go off. A wiggle of the stalk and the high beams come on.
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i have this same problem! low beams are fine but when i click it to highbeam then the headlights just go out.. i just took out my switch and im about to go clean it up a bit which i doubt will actually work.. anyone know where i can get a switch?
#25
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Looking for an old thread of mine, saw this and noticed I never reported the conclusion.
It was indeed both headlight units each with burned out high beams but working low beams. Craziest thing I ever saw, but replaced them back in February and not a problem since.
Very strange, but there it is.
It was indeed both headlight units each with burned out high beams but working low beams. Craziest thing I ever saw, but replaced them back in February and not a problem since.
Very strange, but there it is.
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