Hella Aux Light Question

[TheJackRabbit]

Years ago a pair of Hella Ralley 1000 lights were added up front. They worked great and I rally appreciated the help they gave me.

Recently one light went out and now the other.

The swiitch link is tied into the high beam circuit for th emain headlights.

Fusable link from battery is fine,
relay checks out with good continuity across the closed poles,
There is not power at the leads to the bulbs. No DC Volts.

One bulb, the first one to fail has no continuity across the leads. The other does register continutiy.

Now, does the absence of continuity across the bulb leads indicate a failed bulb that should be replaced?

It is hard to diagnose someone else's installation, but is it possible that a failed bulb would interupt power to the other bulb? Would a failed bulb cauase the relay to overheat and fail.

Any help or ideas short of converting back to coal oil lamps is appreciated.

 

[lovetoski]

I don't think one burned bulb has an impact on the other.

Have you checked to see if there is voltage on the + lead out of the relay? I'm not sure continuity tells you everything you want to know.

No DC voltage at the bulb (you tested the + side I assume?) is where you start, then trace back upstream to find the fault.

I assume your OEM high-beams work?
When you switch the hella's on, does the relay click?

It's possible to lose a ground.

 

[TheJackRabbit]

I have never hear the relay click but then these cars are a bit noisy. THe relay is on the firewall on the engine side.

Now that I think about it, I done a boo boo. When I tested the leads to the bulbs I forgot to ground the negative lead to the multimeter and just stuck both leads from the meter in both leads to the bulb. Duh.

Have to retry it.

Yes, the high beams headlights are fine.

 

[TheJackRabbit]

I don't think one burned bulb has an impact on the other.

Have you checked to see if there is voltage on the + lead out of the relay? I'm not sure continuity tells you everything you want to know.

No DC voltage at the bulb (you tested the + side I assume?) is where you start, then trace back upstream to find the fault.

I assume your OEM high-beams work?
When you switch the hella's on, does the relay click?

It's possible to lose a ground.

If the relay is not getting power, the circuit will not close so I can test power out, right? Also, do these Hella relays have an audible click?

 

[lovetoski]

If the relay is not getting power, the circuit will not close so I can test power out, right? Also, do these Hella relays have an audible click?

Correct on both counts.

If I understand your setup, your relay is on only when your highbeams are on, and your switch is on. This is when you need to measure power out.

All relays I have for lights make an audible click when the internal "switch" is energized by the coil. Prolly need to have the engine off to hear it, but battery power should be enough if it's in good shape.

Questions that need answers...
Does the relay work as it's supposed to, on/off, etc.
Is there power out of the relay? (power to the lights)

My friend Occam still suggests the bulbs are burnt out.

 

[TheJackRabbit]

Correct on both counts.

If I understand your setup, your relay is on only when your highbeams are on, and your switch is on. This is when you need to measure power out.

All relays I have for lights make an audible click when the internal "switch" is energized by the coil. Prolly need to have the engine off to hear it, but battery power should be enough if it's in good shape.

Questions that need answers...
Does the relay work as it's supposed to, on/off, etc.
Is there power out of the relay? (power to the lights)

My friend Occam still suggests the bulbs are burnt out.

Yeah, Occam and his fxxxing razor!!! I pulled the bulbs from their housing and they test for continuity using a multimeter. I cannot see a break in the wirining, as small as it is.

I suspect the relay and will attempt to replace that. I will also buy an extra bulb and try that just because Occam is usually right, all other things being equal....

Thanks for the advice.