I 've never had to replace one so I don't know, I suppose a salvage yard would be the best place to find a complete cluster.

When my car sits for a while, the battery light comes on and stays on until I rev up the engine, then it goes out.

yours staying on all the time tells me the battery, the alternator, or something else is bad.

I would try substituting the battery first. No change? Then remove the alternator and have it tested. No change? look at the cluster diode and test it.

PS: Doug is correct, it is a resistor. It looks like a chewing gum chiclet.

 

Let's backtrack a bit.

1) From post #8 we know that the alternator is working: 14+ volts at battery with engine running.

2) The bulb is always glowing with the key 'on' so we know

2a) one side of the bulb is getting 12v "+" from somewhere, presumably the "ignition feed" as shown in the diagram, as it should
2b) one side of the bulb is grounded or it wouldn't glow at all

3) We don't know where the ground is coming from.

3a)We know the ground isn't coming from the alternator because the light stays on even if the wire is disconnected from the alternator.
3b) We know the ground isn't coming from damaged wiring at the front of the engine, as that wiring has been replaces
3c) We don't know about the remainder of the wiring


More wiring inspection is in order. It may be time to look for a wiring fault in the dashboard area

Cheers
DD

 

The battery charges at low rpm and high rpm. So the alternator and battery seem fine. it’s the warning light. So how about I just pull the damn bulb out?

 

No!!!

That might eliminate the "exciter" function and the alternator would not work. Well, it might in single wire fashion, that is to excite itself on revving up a bit. but suffer no volts at idle??

Get out your S57 schematic and study that dircuit for clues as to why volts presnt when they shoulf not be??/

 

I tested the alternator at the spade connector it reads 14.25. I plugged in my new wire and tested it at the end. It tested 14.25. I plugged the old wire in and tested it at the multi connector. Nothing. So clearly the old wire was bad. But this does not explain why when the new wire is connected my light is still on. It should solve the problem. I also assume that when I start the car even at idle my battery should charge at 14 plus volts . If it’s NOT doing that then there is a possibility that the “exciter” as you call it is not charging at below 2000 rpm. If that is the case is this a function of the alternator or simply wiring somewhere?

 

First, better auto electricians than I please correct me if I go astray!

There are two posts on the alternator. A large brown one. it goes to battery +, via the post on the firewall just under the battery, on LHD cars. That is the charge circuit, regulated on thes cars internaly in the alternator.

And another much smaller wire, color not recalled, it goes to the igniton switch and light on the dash. This is the "exciter: circuit. The key sends the signal volts and awakes the alternator and it charges.

If this wire is not present, the alternator will not charge immediately on engine start. But, a bit of throttle it will excite and charge and keep charging, til the next off/on event.

I don't know if your tests included running or not running the engine. and, idle or throttled up.
And, it is possible that a high idle would excite the alternator even if the excite circuit wsas no working...

So, no complete answer here...

Carl

 

Thanks for your help. Now that there is a good wire going to the warning system it is charging at both low and high rpms. So that’s something. I’m wondering if there is some kind or “reset” after a failure necessary to get the light to go off? Though the system as explained to me by you folks ought to just start working if power is getting to the lamp. I could try disconnecting and reconnecting the battery except I have a battery cut out switch which I use whenever I’m not running it. So that ought to do the same thing. And turning the power off hasn’t changed the situation.

 

have you checked all the fuses inside the cabin?

you were messing with electrical harnesses for the washer pumps. One of them you say is not working or stopped working.

there could be a relation between that pump wiring and the battery / alternator light.

 

I’ll check em all.