Ignition Switch problems

kwutzo

New Member
Mar 13, 2008
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Norman, OK
A few days ago I was in my car when I saw a spark down by the ignition switch. The car continued to run, but I didn't want to risk anything so I turned it off immediately and looked to see what could have caused it. Well, I discovered that one of the wires coming off my ignition switch (black with yellow stripe) had become frayed/exposed, and appeared to have shorted across to ground. I unplugged the ignition switch, repaired the wire, and tested the resistances with a multimeter per the TSRM. They were out of spec, so I ordered a replacement switch. While waiting for the new switch to arrive I decided to check all of my fuses just to make sure that they were ok. They all checked out, so I was hopeful that when my new part arrived the car would start and run like it had before that spark.
Well, the part arrived today, so I checked it to make sure it was the right one, it matched the worn out switch exactly. So I plugged it in and the car still won't start, or even turn to the accessory position. When I put the key in with the door open, the buzzer sounds, but when I turn the key, the car does absolutely nothing. No gauges, no radio, no clock. Also, my power locks stopped working at the same time.
I was curious if it could be a security system issue, since I have the factory alarm hooked up, so I armed it with the key in the passenger door, and opened the driver door, and the alarm went off. When I tried to put the key in the ignition to disarm the horn, nothing again. However, when I relocked/unlocked with the passenger door the alarm turned right off.
I really need this car to be running again since the weather is set to turn bad here in OK again in a couple of days, so if anyone can help point me in the right direction I would be eternally grateful.
 

cuel

Supramania Contributor
Jan 8, 2007
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Baytown, Texas
Dumb question, but did you plug in the connections? Is the switch aligned correctly with the tumbler?
 

kwutzo

New Member
Mar 13, 2008
17
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Norman, OK
Properly aligned tumbler, and made sure connections were good. No loose wires etc...Part of the confusing nature of the problem is that the car does detect the key in the ignition, it just doesn't seem to recognize when the key is in any position other than off.

I'm trying to figure it out, but my school schedule leaves me with little spare time at the moment. Is it possible that the short from the exposed wire touching metal may have caused problems with the ECU? I'm only wondering that because all of the fuses in the driver's side kick panel and the junction box under the hood are still good. But there is obviously an electrical malfunction. What is the best way to isolate the source of the electrical problem since all connections are good? The car was running when the short occurred, I turned it off myself, and following this, the car won't turn back on, or even crank.
 

jetjock

creepy-ass cracka
Jul 11, 2005
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kwutzo;1508712 said:
....Part of the confusing nature of the problem is that the car does detect the key in the ignition, it just doesn't seem to recognize when the key is in any position other than off....

Allow me to clear that part up for you. Key detection is a completely different circuit than ignition. It's nothing more than one wire that gets grounded when the key reaches the bottom of the cylinder.

You know, some time with a meter and the schematic would quickly track the problem down. Or should I say problems as a bit of circuit analysis reveals you have multiple issues. Course, that opinion is formulated solely off your description of the symptoms.
 

kwutzo

New Member
Mar 13, 2008
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Norman, OK
I figured that I probably had multiple issues, I was hoping that someone could help direct my reading/research into the problem since I'm stuck riding my motorcycle in 30 degree weather right now while the car won't start.
I want very much to learn how to diagnose and repair these electrical issues, I typically don't like to try and take short-cuts, I want to understand how a system works and why it breaks to make my repairs of that system more efficient and complete. The time-urgent nature of this problem is the only reason I'm asking the community on here for help. I really can't afford to be without four-wheeled transportation when these forecast winter storms hit in the next few days.
Is there a more detailed schematic available than the ignition page from the TEWD on cygnusx1.net?

Until I find a better approach I'm going to be reading the TEWD and trying to figure this out, any more ideas or links to instructional material that will help me develop my skills would be appreciated!
 

jetjock

creepy-ass cracka
Jul 11, 2005
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The EWD is very well done and contains everything you need. There is nothing better. One needs to learn how to use it though.

I'm assuming the 86.5 model year has similar wiring to the 87. I hope so because the 87 and 89 prints are all I have to go on. At least the wire colors for those circuits seem to be the same.

What stands out here are the inop door locks since the power required for them comes from upstream of the ignition switch. That tells me the 40 amp link in the engine bay box is bad. That would also cause a loss of power to the other items you mentioned. However, since the key warning buzzer is working, that link must be good. So is the ignition switch.

Does the seat belt warning light illuminate with the key on and belt unlatched? Does it and the beeper go off a few seconds after the key is turned on? Do the brake and tail lights work? How about the windows and wipers?
 

kwutzo

New Member
Mar 13, 2008
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Norman, OK
Ok, I checked the 40 amp link under the hood and it did turn out to be broken. I replaced it and am now to the point where the car turns over but doesn't start. As you asked earlier, the brake lights are not functioning, and the seatbelt light doesn't illuminate either. The windows are functioning however.
 

jetjock

creepy-ass cracka
Jul 11, 2005
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Well, that's good to hear but I can only hypothesize based on the symptoms you report. That and you need to check stuff more carefully. All fuses in the left kick panel good? Does the dash now light up? CEL come on? Radio? Wipers? Battery light? What else isn't working besides the brake lights?

Do the door locks now work? They should if the windows work...
 

kwutzo

New Member
Mar 13, 2008
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Norman, OK
Everything appears to work again with the exception of the tail lights and the seatbelt indicator. The CEL doesn't come on at any point however.
 

kwutzo

New Member
Mar 13, 2008
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Norman, OK
I was re-checking the fuses and such to make sure that I didn't miss anything else, and when I opened the 30A fusible link right next to the 40A it virtually disintegrated in my hand, so now I'm off to replace that. Thanks again JJ for all your help!
 

kwutzo

New Member
Mar 13, 2008
17
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Norman, OK
Problem solved and an important lesson about checking fusible links re-learned! Thanks once again to the invaluable advice of jetjock, a supra owner's 911 indeed!
 

jetjock

creepy-ass cracka
Jul 11, 2005
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Good on you. Just took a bit of persistence.

Mike: I do what I can but it's tough to deal with even simple stuff from afar. The irony about electrical issues is, as I've said before, that there are no other class of problem on the car where the solution is so clearly spelled out. All it takes is a meter and the schematic. With a little effort both are easy to operate. Getting people to make that effort is another story.
 

kwutzo

New Member
Mar 13, 2008
17
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Norman, OK
I really appreciate your style of help. You don't just tell people how to fix it you also try to help them think about the problem and figure things out for themselves. It doesn't help to just tell people the solution if they can't develop the skills to solve the problems on their own in the future. You never know if the type of problem might happen somewhere you don't have access to the Internet and jetjock's knowledge.
 

IJ.

Grumpy Old Man
Mar 30, 2005
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kwutzo;1509361 said:
I really appreciate your style of help. You don't just tell people how to fix it you also try to help them think about the problem and figure things out for themselves. It doesn't help to just tell people the solution if they can't develop the skills to solve the problems on their own in the future. You never know if the type of problem might happen somewhere you don't have access to the Internet and jetjock's knowledge.

Finally someone that "Get's it" :D <golf clap>