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sc91gt
12-28-2013, 11:21 PM
Okay, background: 90 sc auto, 170k+ on car 60k motor. Ran and runs great normally... I have been running high beams all the time because the bracket is busted and they are yellowed. It has been almost 4yrs. I have new bracket,headlights and nose to install.

So, since I've owned the car the turn signal/multifunction switch has been bad. Intermittent wipers work for a sec then go to ON. Only way to shut off is wait till down stroke and turn to 0. So I got a JY switch and better for a bit then the same. Now 2yrs later I have a brand new multi switch, ignition switch and the same problem and then some! The other night I was driving home from work, about 1.5hrs with highbeams on and hit the turnsig to change lanes and headlights went off. then back on when I let go of turn indi. Also engine cutout for a sec. Then flicked on and off again. I switched to low beams and ok the rest of the way home. Next morn had to drive 70 miles in the rain and even in low beam, hit the wipers and the headlights and motor cutout for a second and then back on. Like ignition was cut... No intermittent just on until I turned to0 on the downstroke to them to shut off.

I had to replace a melted headlight switch harness early on and have a new switch just in case. Anyone have similar issues? Been driving it with lowbeams but wipers are still FD

TBirdSC89
12-30-2013, 12:27 PM
Not sure about this but would the ignition switch itself cause this? I know when they wear out they start causing a lot of issues

good to doo
12-30-2013, 12:48 PM
Not sure about this but would the ignition switch itself cause this? I know when they wear out they start causing a lot of issues

when my ignition switch failed on my 95, the car would not start and there was no power at all ,completely dead. thanks.

sc91gt
12-30-2013, 04:35 PM
I have installed 2 different new ignition switches and doesn't change a thing. The problem is becoming consistent so I figured I better ask. It seems to be with multifunction,(new or used) or headlight switch?

RalphP
12-31-2013, 01:39 AM
You may have multiple problems dogging you.

The wipers - there's a switch on the wiper motor armature that feeds the "interval governor" (the unit that enables intermittent wipers) so that it can park the wipers when the power's off.

The switch may be bad.

The interval governor may be bad.

The MFS may be bad.

Any of the three can cause it to keep wiping.

Parking in the wrong spot? More likely the switch on the wiper motor (note: replaced as part of the wiper motor assembly) but can be the interval governor.

The headlights - if you get power into the MFS (i.e., low beams or high beams work in any position of the dimmer switch), it's most likely the MFS or downstream, not the headlight switch itself.

At this point, it becomes useful to examine the schematics for the affected circuits in the EVTM that you should have (for about $20 on Ebay or from Helm Inc, it's cheap and helps troubleshooting). If you don't want to buy one, you can get the same from AllDataDIY.COM for about that same $20 for one year.

RwP

KMT
12-31-2013, 01:58 AM
So, since I've owned the car the turn signal/multifunction switch has been bad. Now 2yrs later I have a brand new multi switch

Have you confirmed the right one is installed? Does your car have an auto headlight switch in the dash bezel? Do the fog lights work?

Remove the MFS to check the part number on the (blue or green?) plastic connector/housing - what is the color and does it say AAD, BAD, or CAD?

sc91gt
01-10-2014, 09:23 PM
Today I was driving down the Hwy minding my own business and the wipers came on on their own. Couldn't get them to shut off. Shut car off at a stop light and wipers stayed off when I started car but wipers started on their own again 5 mins later, all the way home. The problem has been with original multi switch, JY switch, and now new switch. All with same numbers. Standard headlight switch, and fog lights did work but have not checked lately. RalphP, Can the interval wiper sitch thing on motor be replaced?

sc91gt
01-13-2014, 08:39 PM
Well for now I am going to rainex the windshield and pull the fuse.. :mad:

RalphP
01-14-2014, 12:38 AM
Have you swapped the interval governor yet?

The switch is an integral portion of the wiper motor, so yes, but you swap the whole wiper motor to do that. I'd try the governor first ...

Alas, only source I know of for the governor is the wrecking yards.

RwP

sc91gt
01-14-2014, 01:50 AM
Thanks! Where is the interval governor located? And any all years interchangeable?

RalphP
01-14-2014, 10:40 PM
Thanks! Where is the interval governor located? And any all years interchangeable?

The break is 1992 or 1993, not sure which.

It's inside the dash - lemme see if I can find an "exploded parts diagram" with it.

How about this?

http://www.2carpros.com/forum/automotive_pictures/266999_flash_3.jpg

RwP

sc91gt
01-15-2014, 10:59 PM
That is helpful. Do you have a jpeg that I can print? I will hit the JY tomorrow. I am ordering the schematic book.. Wipers have not self started the last 2 times I drove it. Doesn't mean its fixed... I still haven't pulled CB. But today the headlights were on highbeam and 20 mins of driving and they started flickering off and on so switched to low beams and stopped. ?

S_Mazza
01-16-2014, 02:10 PM
It sure sounds like you have a problem with the headlight switch or wiring ... or maybe a bad connection at the battery and fuse box that has high resistance and is overheating over time.

Now, the wiper problem may just be incidentally related to that. For example, if the voltage to that system fluctuates, maybe it is inducing the wiper governor to do strange things. Still, with lack of park, I would strongly recommend checking the wiper motor.

You don't have to take the wiper motor out completely to do a check. It may not be 100% conclusive, but it should give you a good idea of how worn it is. Take the driver's side wiper arm off and remove the cowl panel. Look at the crank arm coming up from the wiper motor through lower cowl panel. Take a small prybar and pry up on the crank, just alongside the wiper motor hub. (Don't use excessive force - the cowl is old plastic after all.) Then try to push it down. If you can detect any play there (say more than 1/32"), then the switches in the motor are probably not making proper contact. It needs a new bushing at least.

sc91gt
02-14-2014, 12:33 PM
Driving to work and ignition just died. No power to anything when I turned the key. Headlights/ dash lights come on, but nothing attached to the ignition. Just swapped in a new ignition switch and nothing... I did have an alarm with remote start installed in the fall. Could that be doing something. Stuck on the side of the road...

S_Mazza
02-14-2014, 07:00 PM
Driving to work and ignition just died. No power to anything when I turned the key. Headlights/ dash lights come on, but nothing attached to the ignition. Just swapped in a new ignition switch and nothing... I did have an alarm with remote start installed in the fall. Could that be doing something. Stuck on the side of the road...

The alarm definitely could be preventing it from starting. I think you will have to test at the interrupt wire coming out of the unit and make sure it responds when you turn off the alarm.

Another thing to check is the EEC ground (right in front of the battery, the small wire coming off the negative cable). If the cooling fan turns on when you switch the key on, that ground path is likely open. (Now, it's possible that the alarm is interrupting it. But I don't know.)

sc91gt
02-14-2014, 08:48 PM
When I turned the key on there was no power to anything. The only thing that would happen was the chime letting me know key was in ignition. Had it towed to the shop that installed the alarm/remote start system and they called back a couple hours later saying they tracked it to a relay that is under the under hood fuse box. 12.5v removed and .3v with it in place. If you wiggle it it will fire up and run. Thank god!!!. I have no Idea what relay this is and would like to bring one to swap out when I pick the car up tomorrow. This relay has been stalking me for a while... I would get the car running again by wiggling the fuse box then secured it with bolt. That was last spring and no issue till today. I thanked the stereo shop profusely for saving me the diagnostic trouble.

KMT
02-14-2014, 08:58 PM
Isn't the only relay in the PCB (Power Control Box) for the horn? Did you mean fuse/fusible link, perhaps?

Here's hoping just that one has failed. If you have a chance, you might want to lift that box and confirm no corrosion on the connections underneath. Good luck in any case and thanks for the update.

59781

sc91gt
02-14-2014, 09:32 PM
According to the shop they said there is a relay under the under hood fuse box causing this. I Have never looked. I was curious to what relay this is so I can bring one when I pick my car up. I am sure they will show me when I get there, But I would like to have one on hand.

sc91gt
02-20-2014, 11:34 PM
The stereo shop thought it was a relay, which was the horn, because they were able to get it started when they pressed down on it, but only for 30 seconds. The fuse panel had 12.5v going in and only .3v coming out on black with orange stripe. So I took the fuse box apart and there was corrosion on the power side. Sanded it and sprayed electrical cleaner down the wires. It has started up perfectly ever since. :).

KMT
02-20-2014, 11:42 PM
That's good news :) Thanks for the followup. You may want to coat those connectors with electrical/bulb grease (dielectric) pretty well to help ward off a reoccurance.

sc91gt
02-21-2014, 09:28 PM
I was just thinking about putting dielectric grease on those this morning. I am going to pick up another fuse box from JY cause some of the plastic snapped during removal on mine.

I still have headlights issue. If i drive for 20-30 mins or more with high beams on, the headlights will shut off. Same if I use my low beams with fog lights on. Click the high beams or fog lights off and headlights come back. Relay?

S_Mazza
02-21-2014, 10:16 PM
There was no headlight relay from the factory. Which may be the problem. There's a lot of current going through the headlight switch (pull knob) and MFS (turn signal etc.). You may have melted connectors and insulation! I would check it ASAP.

sc91gt
02-21-2014, 11:04 PM
Tomorrow I am checking the headlight switch. The harness was fried when I bought the car and put a JY harness in. So I will install the new headlight switch and a new harness if need be. MFS is new too.

I have 15w 5 led fog lights in it. Less draw than factory and way brighter. I have LED park/turn 15w, and LED head/highbeams to install, 25w each. Should lessen the load. The LED Head/Highbeam lights are "daytime" running lights but I will see how they work. Shouid be brighter and half the wattage of regular lights.

RalphP
02-22-2014, 03:17 AM
SC91GT - I'd STILL upgrade to a relay harness, be it bought or home made.

If nothing else, getting a solid 12+ volts to the headlights instead of the voltage drop over the too-small wire is a great idea.

RwP

sc91gt
02-22-2014, 01:23 PM
Where inline would a relay be placed?

Do you mean rewiring headlights from switch with larger wire?

SC91GT - I'd STILL upgrade to a relay harness, be it bought or home made.

If nothing else, getting a solid 12+ volts to the headlights instead of the voltage drop over the too-small wire is a great idea.

RwP

RalphP
02-22-2014, 04:16 PM
SC91GT - I'd STILL upgrade to a relay harness, be it bought or home made.

If nothing else, getting a solid 12+ volts to the headlights instead of the voltage drop over the too-small wire is a great idea.

RwP


Where inline would a relay be placed?

Do you mean rewiring headlights from switch with larger wire?

Well, to buy one, you can buy one like this one for the 9005 lamps (they also make one for the 9006, or you can buy a pair of "universal" units - or better, three!):

http://www.theretrofitsource.com/components/harnesses/morimoto-9005-hb3-relay-wire-harness.html

And no, I do NOT mean "rewiring headlights from switch with larger wire". If I had meant that, I'd have said that. Besides, the main problem is not as much the too-small wire (too-small as in "Excessive voltage drop for longest possible life on halogen lamps"), but the current through the switch. Which always struck me as stupid.

RwP

sc91gt
02-23-2014, 01:36 PM
I will get 1 for both low and high beams. It says that wiring is so simple "even your mom can set it up". But I am not my mom so I may have a few questions.. :D