Lucas WL13 Ignition Warning Light

[my427cobra]

Lucas WL13 Ignition Warning Light

Hi all. My 427 Cobra is a street roadster with the street dash and has the Lucas WL13 (Red) Ignition Warning Light mounted above the ignition (key) switch.

A few days ago I got in the car and turned the key to the first position (before the start position) and the red ignition warning light came on. The red ignition light flickered a couple of times but I didn’t think anything of it. I started the car and the Ammeter needle moved normally.

Yesterday, I jumped in the car to go to the Pismo Derelicts cars and coffee, turned the key to the first position, and, no ignition warning light. The car started just fine but no Ammeter needle motion.

I’m assuming the ignition warning light must have failed and was not “exciting” the alternator/regulator so the system was not charging. So turned off the car and turned off the battery disconnect switch as a precaution.

I’ll take the Lucas red ignition warning light out and bench test it.

Does anyone know what the bulb number is and if/where the bulb is still available?

Thanks for your help.

Cheers
Greg

[my427cobra]

OK. I dug through my file boxes and found my old, I should say vintage, Lucas catalogues, and was able to look up the replacement light bulb for the Lucas WL13 ignition warning light.

The replacement bulb is a Lucas 987, 12 volt 2.2 watt MES/E10.

Seem to be plentiful on e-bay. Some NOS in original boxes.

I'll give that a try.

But if anyone has any other thoughts/diagnostics I would appreciate it.

Cheers
Greg

[DanEC]

I would take the bulb out and check for continuity to make sure it’s bad. Other than that it sounds like you pretty much understand the whole function which I tend to think of as some sort of voodoo process - exciting the alternator/regulator to charge. Maybe need to drop a viagra in the oil. But seriously you may need to take voltage checks to see if the alternator is idling at 12.8 volts or putting out the 14 or so necessary to charge the battery. There are some pretty good trouble shooting threads on the ERA forum on this including one for my car. Patrickt provided most of the guidance.

[my427cobra]

Thanks DanEC.

Yeah. I use viagra for everything!

Cheers
Greg

[krausewich]

Have you done a simple wiring check to make sure nothing disconnected behind the dash or alternator?

MK

[my427cobra]

Hi MK. I'll be removing the switch this morning and I'll double check the wiring connections.

Cheers
Greg

[my427cobra]

OK. Problem solved. And I didn't even have to use a can of Lucas Wire Harness Smoke to refill the harness.

Yes, a defective light bulb in the Lucas Ignition Warning Light socket. Not burned out (blackened) but broken filament. Vibration?

Also a loose wire to the Warning Light (probably dislodged as I was removing it).

Car started just fine and Ammeter needle working as normal. Now for a drive to charge the battery up.

All is well again.

Cheers
Greg