Electrical Problem with 4.0L 89 Jeep Cherokee 2WD

[kmerian]

This morning my 89 Jeep Cherokee did something strange, the radio,
turn signals, windshield wipers (front and back), AC fan, rear defroster, and Horn all stopped working. Now, if I turn the key counter-clockwise to that position (where everything runs off the battery), everything works fine, but once I start the engine, it all stops. I have only had
this Jeep for 6 months and it only has 145,000 miles on it. Any ideas?

[Saudade]

Let's back up a bit. If you turn your key to the accessory position (counter-clockwise) everything works. What if you turn the key clockwise to the ON (but not start) position? Does anything work? If so, then start, release the key back to ON and then everything's out?

[kmerian]

Originally Posted by Saudade

Let's back up a bit. If you turn your key to the accessory position (counter-clockwise) everything works. What if you turn the key clockwise to the ON (but not start) position? Does anything work? If so, then start, release the key back to ON and then everything's out?

If I turn it to the ON position, same thing as if the engines running, no wipers, fan etc...

[WornOutCherokee]

I'd sure be curious if anyone has any thoughts on this. My '88 Cherokee just started doing EXACTLY the same thing. I've got brake lights, dashboard lights, basic functionality (fuel pump, transmission, etc., all work), power windows, etc... but blower, turn signals, cig lighter, radio, etc., are DOA when the ignition is in the "run" position (whether or not the engine has been started). When the ignition switch is rotated backwards to the accessory position, all of that stuff comes alive.

Can't help but wonder if there's a bad switch contact in the column? Whatever relay powers up those systems clearly does work, when hit from the non-running "accessory" postition. Suppose I'll start tearing down the steering column... oy. Any feedback from anyone that's run into this problem before?

[Dale Aeppli]

Originally Posted by WornOutCherokee

I'd sure be curious if anyone has any thoughts on this. My '88 Cherokee just started doing EXACTLY the same thing. I've got brake lights, dashboard lights, basic functionality (fuel pump, transmission, etc., all work), power windows, etc... but blower, turn signals, cig lighter, radio, etc., are DOA when the ignition is in the "run" position (whether or not the engine has been started). When the ignition switch is rotated backwards to the accessory position, all of that stuff comes alive.

Can't help but wonder if there's a bad switch contact in the column? Whatever relay powers up those systems clearly does work, when hit from the non-running "accessory" postition. Suppose I'll start tearing down the steering column... oy. Any feedback from anyone that's run into this problem before?

HI , IT SOUNDS LIKE YOU MAY HAVE A BAD IGNITION SWITCH YOURS IS LOCATED ON THE BOTTOM OF STEERING COLUMN, SHOULD BE ABLE TO REMOVE IT WITHOUT ANY TROUBLE. CHECK THE WIRE CONNECTORS ON THE SWITCH, CHECK FOR SCRAPED WIRES OR LOOSE CONNECTORS HOPE THIS HELPS DALE [email protected]

[WornOutCherokee]

Problem solved. Turns out that it was indeed the ignition switch. This $12 part (at least, that's what I paid for an after-market unit which was in stock at Advance Auto Parts).

The trick here was actually getting TO the switch to replace it. Don't confuse the key/lock cylinder with the switch... the key cylinder just moves a metal rod that travels down along the top left of the steering column (right next to the metal rod that is operated by the high-beam switch that's integrated to the turn signal control). Note that this vehicle has tilt wheel - I imagine that non-tilt model are a little different.

BEHIND the dash board, and bolted onto the top-left suface of the steering column, is the switch in question. It's an assembly about 2-1/2 inches long, but mounted onto the same two bolts is the high-beam "dimmer" switch (which is a white plastic assembly) which has to come off first.

The main adventures included:

1) It's just about impossible to work on this area without lowering the steeing column. To large 5/8" nuts are removed to let the column drop down somewhat. The lower dash panel has to be partially removed first to give you some working room. Even with the column lowered, you're in for some real contortions getting to the switch mounting hardware.

2) Be SURE you're disconnected your battery before you do this... fiddling with the switch assembly, you're likely to simulate putting the key into various positions.

3) Once you've physically removed the switch, you'll need to remove the two wiring connectors - the black one has to go first, THEN the larger one will come out.

4) Putting the new assembly in is a partly blind process - you've got to get the L-shaped ignition push rod in to the matching hole in the switch assembly. It's a little tricky.

So: the problem described was fixed with a $12 part and about three hours of fuss. Whew! Thanks for the helpful comments.

[kmerian]

It was indeed the ignition switch, living in central Texas, it's great to have AC again. Now if I could just get rid of that "death wobble"...