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What Now?!!!

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JPSmit

JPSmit

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well, tonight was progress. Got the reverse light working. got the tranny topped up. Got the muffler re-secured. Changed the oil yesterday and wanted to start it up to get the rad fluid circulating to top it up. Started the car and almost immediately got a loud "hum" that only stopped when I disconnected the battery. In fact the car kept running even when I took out the key. Again, only the battery stopped it and when I disconnected the battery it stopped instantly. The hum seems to be coming from the starter which makes me wonder if it is not disengaging - though I would have thought that would make a grinding noise

any ideas?

Oh and I banged the starter with a stick - nothing changed.
 
There is a square shaft sticking out the front of the starter, see if you can turn it easly with a wrench. It is of all things the unstick trick.
 
There is a diode under the dash that is part of the brake warning light system. If it fries, it will allow current to leak into your ignition and starter circuit. I can't remember how exactly I removed the diode from the circuit, but I think it had something to do with cutting a red/white wire. Study your wiring diagram until you find the diode, then follow the wires until you find the one that goes back to the ignition switch. That's the one that has to go. Or, remove your dash and remove the diode all together.
 
JP;
Where are you in Ontario?
I am a licensed Technician in Ontario and I have time to look at a lot of problems that you have if you're close enough to me.
I'm in the middle of S.W. Ont. close to London

Dave
 
Thanks all - I'll try. Morris yours makes the most sense as I just powered the brake failure circuit. - what does the diode look like? or is it buried in harness wrap?

Dave, I'm in Waterloo - just on the edge of far but thanks so very much for the offer

I'll keep you posted

Morris - if I disconnect the brake failure sensor plug would that isolate the problem?
 
I never found the actual diode as that requires removing the dash. I just deduced what the problem is after studying the wiring diagram. Once I cut the wire from the ignition switch to the diode, the problem was solved. If I get a chance later today I will look at the wiring diagram and car to see if I can give you better advice.
 
I've got the wiring diagram too - and know what you are referring to, I just have not been able to sort out what the EGR diodes and brake diodes etc actually look like - will keep looking
 
I imagine the diodes are buried in the harness somewhere.

After reviewing the diagram I have two possible solutions for you.

1) Find the "time delay buzzer unit," remove it, and throw it in the garbage. I actually would recommend that regardless of your wiring problems. I hate that buzz noise.

2) There are two red/white wires coming out of the ignition switch harness connector. One goes to the start solenoid, the other goes to the brake warning light. If you can figure out which is which, you can cut the one that goes to the brake warning light.

I did both of these, but I cannot remember in what order. I would definitely try removing the buzzer thing first as a test.
 
:winner1: Morris!!!!! Thanks my friend for your advice. It was exactly as you predicted. I disconnected the Brake Pressure Failure Switch and all is well.

Here is my question for tonight (and trust me it would help to have the Bentley 1500 book turned to page 330)

I have disconnected the Brake Pressure Failure Switch (#27) As I look at the diagram, it seems like I could either

A)leave it disconnected (easiest but then I loose the switch)

B)disconnect the YR & WR wires at the diode (#9) if I can find it, leaving the switch intact but loosing the diodes #8, 9 & 10 which shouldn't be a problem.

C)Disconnect the WR wire at the buzzer (#28) which is what Morris seems to suggest. This is connected to the diode #8 and does something.

any ideas?

Does it matter if I don't have a brake failure warning switch?
 
Personally, I think the brake failure does three things, only one of which is truly valuable to me.

The first thing it does is let you know that you are about to slam into the car in front of you because your brakes have failed. I can not see the value in this.

The second is to either reminds you to adjust your rear brakes or check your brake fluid level. Both are a a matter of routine maintenance for me so I feel like I can manage without the light.

The third is to lets you know that you that you failed to fully disengage the parking brake. This is really helpful. I frequently fail to fully disengage the parking brake as sometimes the lever gets bogged down on the side of my big fat butt.

So... it is up to you. Can you live without the brake failure switch?
 
Morris said:
I never found the actual diode as that requires removing the dash.
Click to expand...

found them - they are under the dash above the glove compartment - can't start the car as the alternator is off but should be able to isolate the circuit
 
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