Low beams are not working!

[MrJLR]

My high-beams AND low-beams would work and switch back and forth with the floor mounted switch before I installed my headlight relay kit from crackedback.

But now I only have high-beams...if I step on the switch - the lights go off (low-beams "should" have come on).

Crackedback has been awesome and more than helpful and we checked his parts by jumping off the battery with a wire - his relays and harness all work perfect. I can get both high and low beams by jumping it.

He thinks I have a ground issue somewhere in my original system. Sounds reasonable to me.

I've looked and looked and can't seem to find it! ARG!!!!!

Any ideas or suggestions?

Thanks in advance!

:coffee2:

 

[memike]

Sounds like the switch it self to me if you can jumping at the switch, I have seen new switches that was bad ..

 

[MrJLR]

Sounds like the switch it self to me if you can jumping at the switch, I have seen new switches that was bad ..

Hmmm.....that's possible.
I forgot to mention I replaced the switch too with no results :banghead:

I can try bypassing the switch.....but BOTH the old and brand new switch have not worked.....

 

[mopardude62]

Yea, I agree Crackedback is a GREAT guy!! Have you tried swapping the relays to see if maybe you have a bad relay?

 

[MrJLR]

Yea, I agree Crackedback is a GREAT guy!! Have you tried swapping the relays to see if maybe you have a bad relay?

Yes.....I swapped the relays - no dice....
Checked the fuses....both are good.
Plus, we jumped from the battery to his system and both high and low beams worked.....

Part of the fun with these cars - right?!!!!!

 

[mopardude62]

You know if he thinks it might be a ground issue with your original wiring, can you unplug the wires from Crackedback's relay harness from your headlights and plug your original wiring back into the headlights and see if you have low beams? If you do have a ground issue in the original system, this will show it pretty quickly.

 

[MrJLR]

You know if he thinks it might be a ground issue with your original wiring, can you unplug the wires from Crackedback's relay harness from your headlights and plug your original wiring back into the headlights and see if you have low beams? If you do have a ground issue in the original system, this will show it pretty quickly.

I've considered that.....it's a lot of work but I may end up doing that.
I'm just hoping I find a loose/hanging ground somewhere.....wish I understood more about the circuit. I'm not too hip on electrical...!

 

[67Dart273]

All you have to do is logically think this through and find it. You can't just easter egg it.

Get your meter out and probe relay power to the low beam relay.

1....It should be getting power to the coil when low beam is selected. If not backtrack to the bulkhead connector and probe it there. If not there, then backtrack to the dimmer switch and verify it at the wire coming out of the dimmer connector.

2....Make sure the relay socket coil wire is grounded. Easy. Probe the socket, and ground. Should be close to zero resistance

3...Verify power is coming INTO the relay contact

Since I don't know how these relays are wired, this is only a guess

Hot fused headlight power should be on all the time to 30

coil connection 85 should be ground

coil connection 86 should be hot with low beams selected

If all the above checks good, select low beams and go out and unplug a headlight. You have power there? If not backtrack back to the relay. Should have power to 87 with low beams selected.

 

[MrJLR]

All you have to do is logically think this through and find it. You can't just easter egg it.

Get your meter out and probe relay power to the low beam relay.

1....It should be getting power to the coil when low beam is selected. If not backtrack to the bulkhead connector and probe it there. If not there, then backtrack to the dimmer switch and verify it at the wire coming out of the dimmer connector.

2....Make sure the relay socket coil wire is grounded. Easy. Probe the socket, and ground. Should be close to zero resistance

3...Verify power is coming INTO the relay contact

Since I don't know how these relays are wired, this is only a guess

Hot fused headlight power should be on all the time to 30

coil connection 85 should be ground

coil connection 86 should be hot with low beams selected

If all the above checks good, select low beams and go out and unplug a headlight. You have power there? If not backtrack back to the relay. Should have power to 87 with low beams selected.

Thank you! I'll try all that tonight after work.....
At least now I have some new direction to look!

:coffee2:

 

[MrJLR]

Is there only one fuse (originally) for both the high-beams and the low-beams?

 

[67Dart273]

Is there only one fuse (originally) for both the high-beams and the low-beams?

Yes.

Power for ONLY the headlights comes from the ammeter harness directly TO the headlight switch. With switch on, power goes down TO the dimmer switch. This is a simple 3 terminal SPDT switch, that is, two terminals are always connected, and when you mash the switch, the power and the "was dead" terminal is now connected

One out for hi, and this branches off to feed the high beam indicator

One out for lo

both these wires then go through the bulkhead, out and around to the headlights

 

[MrJLR]

Yes.

Power for ONLY the headlights comes from the ammeter harness directly TO the headlight switch. With switch on, power goes down TO the dimmer switch. This is a simple 3 terminal SPDT switch, that is, two terminals are always connected, and when you mash the switch, the power and the "was dead" terminal is now connected

One out for hi, and this branches off to feed the high beam indicator

One out for lo

both these wires then go through the bulkhead, out and around to the headlights

Awesome....I'm understanding it better now!
Can't wait to get out of work and check it out!

Thanks a bunch!

 

[crackedback]

Have you probed the factory headlight plug with a voltmeter?

Violet hot on low, red on high and there should be no bleed over to either.

I assumed your original set up worked properly. If there is no power to the violet wire, check/probe the bulkhead connector.

 

[MrJLR]

Have you probed the factory headlight plug with a voltmeter?

Violet hot on low, red on high and there should be no bleed over to either.

I assumed your original set up worked properly. If there is no power to the violet wire, check/probe the bulkhead connector.

I will check that too...!