Help! IGNITION SWITCH replacement/access

[boomdriver]

Has anyone had to take the ignition switch out ? (87 c-4 coupe, auto, tilt, telescopic column)
The FSM is a little vague on the procedure and was hoping for some tips and guidance on the process.

I'm having an intermittent problem with the starter....turn the key and nothing happens. Then the next attempt will be ok. Everything points to the ign switch on the column being out of adjustment or simply worn out so I figure I'll just replace the thing and clean up inside there and look for other worn items under the horn button. To be clear, I'm NOT talking about the KEY switch....tumblers and lock mechanism. I am referring to the actual electrical switch that does the work of making contact so that power gets TO the starter and accessories as key position dictates. I have done other vehicles before, but never a tilt/telescopic wheel with a VATS type key. Is this something that CAN be done at home or is it such a PITA that its worth paying a shop a small fortune in labor to change out a $20 switch?


Any suggestions, advice or tips would be appreciated.

Lee

 

[DonB]

I just finished a steering column overhaul on my '90(as part of a complete car redo) and the first thing I'd recommend is to remove the drivers seat(unless you are comfortable hanging up-side down.) Also having the car up on stands makes your access angle to under the dash better. You then must remove the drivers lower bolster(I think it is called.) Lower cover anyway. Then remove the metal cover(the bolster bolts to) underneath it to gain access to the two bolts on the cradle that hold up the steering column. Remove the bolts and gently lower the column
You will then see the ignition switch on top of the column . It is rectangular in shape. BE AWARE the dimmer switch is also down there on the left side of the column.
I would check the action of the ignition actuator rod as you turn the key switch. I mention this because there is a little $5.00 part buried near the tilt mechanism called the ignition rod actuator that meshes with the rod and the key mechanism as it turns.
IF YOUR TILT PINS ARE(or were) WORN there is a strong possibility that your problem is a bent or worn actuator. Dorman sells a replacement but it's a bear to get to.
Steering column service is NOT explained well in the SM and if you have never done it, I'd consult a professional. But according to what you are describing, the actuator WILL jump off the actuator rod and the key switch then rotates and does NOTHING. Leaving you stranded. There are a lot or intricate parts and specialty tools(i.e. steering wheel puller, lock ring compressor, snap ring pliers, to mention a few) involved in dis-assembly and correctly assembling the column.
It wouldn't hurt to drop the column and check the action though. BE sure to remove the ground cable off the battery during dis-assembly for safety.

Sorry to sound like Mr. Doom and Gloom, but it happened to me as well as a few others with the Saginaw tilt column. Saginaw was the company that built the tilt/telescopic steering columns for GM and Chrysler.

Good Luck, Don

 

[ecss]

Depending on how often the problem occurs you could try to isolate where the problem is.
If you have a volt meter or test light you need to take a couple of voltage measurements
when the problem occurs.

If you remove the Driver information center you will see the starter enable relay. The relay is energized
when the ignition switch is in Start and the control side of the relay is grounded by the Vats decoder module.

The schematic shows the four wires that go to the relay.

Large gauge Yellow wire is 12 volts when the ignition switch is held in the Start position.

If no 12 volts could be the ignition switch.
If there is 12 volts it's not the ignition switch.

Small gauge yellow wire is 12 volts to the control side relay coil.
Dark Green wire goes to the Vats decoder module. (Grounded when the proper key pellet is read).
Dark Green/White wire goes to the neutral safety switch or clutch safety switch.

1) When you turn the ignition On you should have zero volts on the Dark Green wire which should be grounded by the Vats decoder module.

2) When you turn the key to Start the relay closes and 12 volts comes out of the relay on a Dark Green/White wire.

3) The Dark Green/White wire goes to the Neutral/Park switch or clutch switch for a manual trans.
Then to a Purple wire which provides 12 volts to the starter solenoid. The solenoid engages and the
starter motor should run.

You can bypass the Starter Enable Relay by removing the relay from it's socket.
Take a paper clip and connect the Large Gauge Yellow wire to the Large gauge Dark Green/White wire.
This also eliminates the Vats Decoder Module from disabling the starter enable relay.

 

[boomdriver]

Thanks DonB for the detailed write up.

figured dropping the column would be the easy way to get at the thing. There is a rebuild kit for the little gear actuator and its rod, $9 at O'Really auto parts. Going to pick that up with the new ign switch $20 and plan on fun fun fun for the weekend... Seat coming out is not a biggie....learned to do that whenever I needed some money. Always a few $$ under there.......

 

[DonB]

if you run into any issues, give me a shout. slow and methodical plus take pictures of it as you dis-assemble the column. compressing the lock ring is a major factor and don't over-compress the lock ring. Depress it only enough to remove the lock ring in it's "race" in the column. get it out of it's race and move it up the column using a fine snap ring pliers and a few long fine screwdrivers. Then release the lock ring and you'll see how it comes apart.
Don