I'm baffled. Relay issue.

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73c20jim

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I understand how 12V DC works. I understand how relays work. But I'm baffled.

I purchased and installed the headlight relay system from I think Classic. It worked fine. For about two years. We have had some HEAVY rain here over the past week or so. The headlights no longer work.

I have 12 V to the always on high amp side of the relay connector. Always on.

I have 12V to the trigger wire of the relay connector when the headlight switch is on.

When I jump the High amp input to the high amp output the headlights go on.

At this point i figure bad relay.

So I buy 6 new relays with the exact same part number. Tried all six. No headlights.

So, I test the relay. 12V to high amp input, No power to any other pin. The ground to the relay connector also works, caused I almost burned my finger off when I touched 12V to it.
I connect 12v to trigger wire, HAVE 12V TO HIGH AMP OUTPUT. The relay works.


The pins from the relay go into the sockets of the relay connector without problem. I can feel them making contact when I insert the relay into the relay connector. The relay locks in place.

Any help is appreciated.

Thanks.

Jim
 

Snoots

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It sounds as though you've eliminated the relays as a problem.
What about the ground to the lights?
 

73c20jim

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BUMP for help.
 

EvilGenius

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Yeah my guess is a compromised ground or 12v signal wire. When you close the connection for the coil it can't handle the load but still shows 12v to a multimeter.

To confirm this run a jumper 12v wire direct from the battery and another jumper wire direct to ground
 

R Carnella

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I would check the relay grounds,do they activate (click) when you turn on the headlights?
 

WesN

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Relay terminal 30 12v + live
terminal 85 12v + switched
Terminal 86 ground
Terminal 87 12v + output
terminals 86 and 85 can be reversed
terminal 87a is normally connected to 30 but open when 86&85 are activated
 

mshawn

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Relay terminal 30 12v + live
terminal 85 12v + switched
Terminal 86 ground
Terminal 87 12v + output
terminals 86 and 85 can be reversed
terminal 87a is normally connected to 30 but open when 86&85 are activated
This is the correct information on the relays. When all the head light are of you should have power at the #30 on the relays. Reverse your test light from the clamp on the ground to clamp at positive post of the battery. With the relay unplugged from the connector touch top of the test light on the connector that gos on pin 86 if it lights then you have ground.if it doesn’t then you have lost your ground. It in those situations both power and ground are there then we will move on to turning on the headlights. When you turn on your headlights, you should get power on #85. If you don’t then you have a bad headlight switch, in turn means none of the lights are going to work. If you do then headlight switch is good. In that case you need to check for ( with relay installed, power on #87 or # 87a depending weather it is on high or low.if all that is good , you need to check for power at the headlight connector at headlight. You can use a test light or a power probe or digital volt meter to test. Let me know if this works. If you don’t find your problem them hit me back and we will go further to find the problem
#30 power all the time
#85 power when headlight switch is turned on
#86 constant ground
#87 output power to your headlights when switch is on
#87a output power to headlight if not on 87 when switch is on
It all this is good then we will go then next steps. I think you will find your problem in this diagnostics
I hope this helps. You can use this as a start to test every relay in most systems 12v

Mshawn
 

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