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Discussion Starter #1 (Edited)
I just bought an 86 900s -- fourth Saab. Only 60,000 miles on this garaged car, but it looks like I got passed a conundrum. Tonight, in the rain, strange magic in my electrical system, including:

1)No headlights and when they are on I can't flick on high beam either. There are parking lights. When I shut off the headlights or leave them at parking light, I can high beam the lights. But if I turn the switch to headlights my high beams shut off immediately!:cry:

2) There has been another problem in the past couple of days too. Sometimes when I turn on the ignition the parking brake does not go out. At the same time, the windshield wipers, the heater fan, the turn signals, and the rear window defrost don't work HOWEVER, if I hold the emergency flasher switch in about half way, everything works. If I let go immediately it fails, but if I hold for about five seconds, then everything works fine, Except for the headlights.:roll:

Two days ago I had it pre-safety inspected while getting tires. They had to order a muffler but said it would pass when that was installed. Now I have these occult electrical problems. Sheesh.:cry:

I have a feeling I have a ground short somewhere -- one thing is causing all things, because sometimes the electricals work fine at startup and sometimes they don't.

The headlights must be something separate.

Anyone have any ideas? I am really lousy with electrical testing and reading wiring diagrams. Thanks:confused:
 

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You should really take it to a sparky who can diagnose the problem in a few hours without too much drama, it could be any number if silly little things to something we just can tell from a far.
 

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Pull out the Ignition Lock Relay in the fuse box, and check for burned, corroded, melted connectors.
 

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Discussion Starter #4
Thanks for the advice. I took it down to a garage this afternoon. My neighbor decided to help me diagnose and he's a bit of a terrier. First thing I knew he had the dash out looking for ground number 3, which he never found. Did tear apart the clutch master cylinder however. Probably while removing the cardboard shroud over the pedals. So now I have real problems. BTW anyone have any idea how to remove the lower air distribution shroud (I've four screws out but it seems to be mounted invisbly in the center. Saab 900 s 1986.
 

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You have to remove the centre console too. However, to get at the clutch master, you could just bend the air duct down out of the way...
 

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Discussion Starter #6
I have removed the centre console but that duct still wants to stay locked up there. There is a padded bar that runs across the front of the car directly below the instrument cluster and dash panel. I don't know how to get that off and I think it is the key and there are no directions.
 

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saaboholic said:
I have removed the centre console but that duct still wants to stay locked up there. There is a padded bar that runs across the front of the car directly below the instrument cluster and dash panel. I don't know how to get that off and I think it is the key and there are no directions.
there is a large bolt behind the ashtray. there are two more accessible once you pop the hood and look down in front of the doors, behind the fenders. if the plastic drain hoses from the slot behind the hood are still there, the screws are tucked in just behind them, down maybe 5-6 inches.

off the top of my head, i've no idea where the headlights are grounded. i might presume at the lower radiator cross member? that is a classic problem area, i would check the wiring there and clean those contacts.
 

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Couple things to check

First off it sounds like a bad ground behind the instrument panel... the one I think you were looking for.

I also might suspect that your dash cluster circuit board (that is behind the instrument cluster) may have become cracked/detiorated. If you turn on turn signals, does the temp/fuel gauge bounce up and down? that's a dead ringer for a poor or decomposed circuit board. If you get really lucky, it might not be the circuit board and could actually be one of hte two long vertical connectors on either side of the cluster. You can see these connectors if you remove the drivers side speaker grille and look really closely.

The ignition lock relay's a good thing to check.

You could also have a bad connection at one of the main multi connectors under the fusebox. I think on the 86 models they're called 152A, 152B and 152C. They are the master connections that go from inside the interior through the firewall side area to the fusebox. WIggle them and see if it helps.

Short of that, I would check the ground at the front radiator crossmember, if you stand on teh battery side of the car, look at the battery, then look from the battery following the negative (blue) battery cable down to under hte radiator fans, you'll see it there. Sometimes its a corroded mess or the bolt has stripped. If either is the case, you should remove, retap, reconnect.

Hope that helps !

(ps - and to get your lower duct out, you dont have to remove the underdash pad. it as 2 screws that hold it to th efloor heater duct if i'm not mistaken.... but all that is underneath the carpet). you should just BEND the lower duct down and tuck it under the brake or clutch pedal, will work fine that way)
 

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Discussion Starter #9
Thanks problems solved

many thanks.


It now appears that I had a bad "Ignition Pulse Amplifier" and a bad headlight relay. All problems seem to be gone, although I have put a simple relay where the pulse amplifier was. They seem to be hard to find.
 

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Discussion Starter #11
Do you mean what they call the "Ignition Pulse Amplifier" on Saab 900 models 1986 and 1987? I have one on the way but it's used.
 

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saaboholic said:
Do you mean what they call the "Ignition Pulse Amplifier" on Saab 900 models 1986 and 1987? I have one on the way but it's used.
No. That can only cause a no start condition. It was thought that the ignition pulse would be too weak after being bussed all over the car for different functions. There was a service bulletin on how to bypass it after it proved unnecessary.
The Ignition Lock Relay shuts off many functions when the starter is engaged to provide maximum power for starting. It has large terminals that can overheat and melt the relay panel. See the first post of this thread for an exact list of symptoms.
 

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Discussion Starter #14
Ignition Switch or IGNITION LOCK RELAY?

In my Bentley there is a spot next to the AC/Ignition Pulse Amplifier that is called the "Ignition Switch". Is this what you mean by (and also what is elsewhere referred to as) the "Ignition Lock Relay". If so, it appears that the previous owner had put an "Ignition Pulse Amplifier" in the Ignition Lock Relay slot. Hence the strange and inconsistent failure of electrical systems.

But Jim am I right that the "Ignition Lock Relay" is what the Bentley calls the "ignition Switch" on the relay panel?
 

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saaboholic said:
But Jim am I right that the "Ignition Lock Relay" is what the Bentley calls the "ignition Switch" on the relay panel?
I couldn't tell you, I haven't seen a Bentley manual in 20 years.
The Ignition Lock Relay ( the correct name) and socket are identifiable by their larger blade size.
 

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Sometimes, a picture is worth a thousand words (this may or may not be one of those times). I hope this helps.
the ign. relay in this pic is the white blur in the middle of the fuse/relay panel.

It is easily recognized by its unusually large blades.

Fuse/relay panels were changed many times over the years, the example shown is a 1988 spg.
 

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<off topic>
Grif, is that a light switch on the frame next to your fuse box?
</off topic>
 

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Discussion Starter #18
Okay Grif thanks. Here's what happened. The previous owner had the ignition pulse amplifier plugged nto the ignition relay. hence the circuit was cutting out under most circumstances. The pulse amplifier has the same pins as the pulse relay. It sits next to it. Now another question. If Saab had directions in how to bypass the ignition pulse relay, how do I obtain that bulletin or those instructions? thanks
 

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jglavin-the switch is for the alarm.
saaboholic-Townsends site lists some tsbs, perhaps its there. Or Jim may enlighten us.
 

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Discussion Starter #20
I thought I should make really clear what happened in case someone else falls into the same trap some time down the road. I have seen (on Ebay for example) people selling the old style "Ignition Pulse Amplifier" but calling it an "Ignition lock Relay". My guess is the last owner burned out his "Ignition lock relay" and accidentally replaced it with an "Ignition pulse amplifier" thinking it was an "ignition lock relay" then had the problems I have had and never figured out the mistake, hence the low price I paid for the car. Jim is really right -- the first thing you have to do is switch out that "Ignition Lock Relay". Would have saved me a lot of headache if I had listened. Plus the photos above helped too. Thanks all, the car runs perfectly now that I have my steel braided teflon fuel lines on it.
 
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