Ignition switch vs ignition lock

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snapped01

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Hey guys my starter is having issues where it will stay on even if i pull the key out so the only way to get it to stop turning is disconnecting the battery. Now i took the starter back to the parts store and they tested it so it was fine.

I know my ignition lock is the part where i put in the key but where is the switch located? I see tons of videos on youtube on replacing the ignition lock but none on the switch. Can anyone give me some insight on how to replace the ignition switch?
 

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It near the floor board on the steering column
 

yevgenievich

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It is on top of the column under the dash. Generally accessed by dropping the column down
 

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The neutral safety switch is towards the bottom.
 

chengny

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This was written for a guy who had the opposite problem, he had to really crank on the ignition lock to get the switch into the START position. He was just looking to adjust the switch. Ignore the parts that don't apply.

Accessing and changing the switch is easy and shouldn't take more than an hour or two.

The column has to be dropped is because of it's location under the dash support bracket. It is intentionally made inaccessible for anti-theft reasons:

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It shares a mounting clip with the high/low beam switch:

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The GM procedure for adjusting/replacing the switch is at the bottom. Some other hints on dropping the column for access first:


I start in the engine compartment by releasing the transmission gear select connecting rod from the crank arm on the intermediate shaft.

Back in the cab, the lower column trim cover and dash filler plate come off:

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With those removed, you'll be looking at this - except your bezel and IP will still be there:

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To drop the column you'll need to release the clip on the end of the gear indicator wire:

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From where it clips to the bowl shroud. Do it now, so you don't forget:

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Then just release the two nuts that secure the column bracket to the instrument panel support:

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Depending on how tight your wiring harness is, you might have to unplug it from the column. But usually there is plenty of slack for the steering wheel to rest on the seat without pulling any plugs.


Lower the column until the steering wheel rests on the seat and adjust/replace the switch as necessary.




Removal procedure per GM:

1. Disconnect battery ground cable.

2. Disconnect and lower steering column. Only lower steering column a sufficient distance to perform ignition switch service.

3. Rotate ignition lock to the OFF "locked" position.

4. If lock cylinder has been removed, pull the switch actuator rod up to stop, then down
to the first detent position as shown, Fig. 7.


5. Remove column mounted dimmer switch, if equipped, then remove switch retaining
screws and switch.

Reverse procedure to install, noting the following:

1. Place gear shift lever in neutral.

2. Place lock cylinder and ignition switch in positions noted in step 3 & 4 above.

3. Fit actuator rod into hole in switch slider and secure switch with retaining screws,
ensuring switch does not move out of detent.

4. Install and adjust dimmer switch, if equipped

5. Torque retaining screws to 35 lb in, then check switch operation.

Those are probably the worst instructions I have seen in a while.

Anyway, since I was looking at doing this job soon myself, I checked which way the rod moves - in relation to the rotational direction of the lock cylinder.

If rotated CW (START) the rod moves toward the switch. And if rotated CCW...

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snapped01

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So i replaced the ignition switch but i still have the same issue. The starter keeps cranking even when the key is off. This is a new starter and new ignition switch.

I proceeded to test the purple wire on the starter and it is still getting voltage even when i turn the key off. What is my next move? I am stumped.
 

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adjust the switch. the new switch should have come with adjustment instructions or get them from a manual. highdesertranger
 

chengny

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Just to be sure, please clarify something first.

When you say this:

The starter keeps cranking even when the key is off.

it will stay on even if i pull the key out so the only way to get it to stop turning is disconnecting the battery.


They both seem to indicate that the problem with the starter is like this - It won't disengage and stop cranking when the ignition switch has been moved from OFF to START and then back to RUN. It won't even stop if turned to OFF again. To get it to stop the entire system must be disconnected from the battery.

What you don't specifically mention is what happens when system power is restored after one of these incidents. What happens if the starter is shut down by taking the positive cable off the battery and then, at some later point, the battery cable is reconnected.

On the assumption that the key/ignition switch is still in the OFF position - left there from the last attempt to kill the starter - what happens when system power is restored?

As soon as the battery is connected, without you touching the key, does the starter immediately engage and begin cranking the engine?

Or, after the power is restored, does the starter remain de-energized like normal? And it is only after the key/switch has been moved to START - and is then released back to the RUN position - that the starter doesn't react and shut down?

I guess the basic question to ask is this; Does the starter only fail to shut down after you have operated it or does it self-start whenever power is available?

Considering that you're good enough to change the ignition switch quickly, without any other questions - and using only the crappy instructions above, it's probably safe to skip the obvious. By that, I mean you set the switch properly in relation to the lock cylinder position. Also while the column was down, you checked that the link rod was able to stroke freely up and down, that it wasn't bent and that the lock cylinder rotated smoothly from stop to stop.

When you release the key, can you feel it spring back into the RUN position? Can you get the starter to disengage if you rotate the key past RUN, past OFF and all the way back to ACC?

With a new switch - that is properly adjusted - and a link rod/lock cylinder that are free to move axially, it might be the case that there is a short in the purple lead to the solenoid. Do you have an automatic or manual transmission?


BTW - it is always helpful if you provide a little background on the issue at hand. For example, whether it came on all at once, got worse over time or has always been there. Another key thing to mention is what work - if any - you did on the truck in the period before the problem started.
 
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snapped01

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Thanks for the response Chengy.

A little background, my starter went out one day where i would just hear a loud click. I replaced that starter but when i installed the new one, the continuous starter issue began. It would not stop cranking! I took out that starter thinking there was something wrong with it so i got it tested at auto zone, came back fine. I installed it again and no more starter issues! After a while i kept on hearing this awful grinding noise. I investigated it more and noticed that the starter had the wrong number of teeth for my flywheel. I got a new starter but the same issue occurred again with the continuous cranking.

So I just went out there last night to perform some test you told me to. I still have my steering column resting on my seat so i have direct access to the ignition switch. I am operating the ignition switch with a flat head screw driver and just moving it between off, acc, run and start.

I can feel the mechanism in the ignition switch spring back to the run position after i crank the starter so its not an issue there.

On the assumption that the key/ignition switch is still in the OFF position - left there from the last attempt to kill the starter - what happens when system power is restored?

When i reconnect the battery nothing happens, it stays off.

Or, after the power is restored, does the starter remain de-energized like normal? And it is only after the key/switch has been moved to START - and is then released back to the RUN position - that the starter doesn't react and shut down?

Yes exactly!

I was able to jiggle the wires going into the ignition switch and that seemed to do the trick, it slowly stopped the starter from cranking. However i repeated the test and same thing. I had to jiggle the wires again for it to stop. What should i do from here? How would i be able to locate the short? I traced the wires from the ignition switch and they seem to go into the fusebox. I have no idea where they go from there.

My truck is a manual transmission.
 
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chengny

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Okay,

1. The switch is new (assume no internal electrical problem there).

2. If you are absolutely sure that nothing in the external switch operating mechanism (i.e. the ignition lock cylinder, cross shaft, gear, sector and link rod) is binding - and causing the switch internals to be unable to move backwards - when the key is released to RUN, we can eliminate all that stuff.

But if any of that linkage is somehow preventing the switch slide from moving back and opening the START contacts (i.e. most forward position) with the key released, battery power will remain connected to the purple (in your case yellow) wire.

So after eliminating a bad switch and any problem in the switch operating linkage, it would suggest that the lead going to the solenoid is shorted to battery voltage somewhere after the ignition switch.

You are going to have to ring the circuit out. With any luck, you have access to a multimeter and know how to use it.

When you have your meter ready, pull the plugs off the ignition switch. You'll be checking the terminals that connect to the bigger plug - the one with 5 leads. Here are the two terminals you be concerned with:

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First, make sure that the START contacts are opening and closing as designed. I know the switch is new - and you are certain the linkage is not binding - but please, humor me.


1. With the key in the OFF position, confirm no continuity between the battery supplied terminal (red tracer) and the power to the solenoid (yellow tracer). With a manual transmission, the purple wire to the solenoid starts off as a yellow lead. It changes to a purple lead after passing through the CSS (clutch start switch). If that test shows infinite resistance/OL (or there is no beep - if using the audible continuity function), those contacts are open. That's correct.

2. Next check that the start contacts close correctly. With the meter's probes on the same two terminals as above, move the key to START and confirm zero resistance (or a constant beep in audible).

Do those tests and see what you get.
 
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yevgenievich

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Have you verified that two terminals on the starter are not making contact?
 

chengny

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Here is the starting circuit wiring diagram. It's pretty simple. Battery voltage into the ignition switch on the red, out on the yellow when in START. Into the CSS on the yellow and out on the purple - with the clutch pedal depressed. Purple goes through the firewall and straight to the starter solenoid:

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If the solenoid is not disengaging, there is a problem with one of these:

1. The ignition switch

2. The interconnected wiring. External voltage is being applied to the yellow/purple lead somewhere between the SOL terminal of the ignition switch and the "S" terminal of the solenoid.

3. The starter/solenoid itself. It's possible that an internal short is being created that connects the main battery connection on the solenoid to the power supply for the solenoid. It is created when the solenoid pulls in normally and then stays connected even after the power is removed from the purple wire.


Problem with #'s 1 & 3 is - both components are new.

Problem with #2 is - if that condition did exist, it would be extremely rare.
 

chengny

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I was going to go with one of these...an improperly adjusted ignition switch or restricted motion in the switch linkage.

But then I saw the history Kevin posted and - after reading it carefully - I'm not so sure it's an electrical issue.

A little background, my starter went out one day where i would just hear a loud click. I replaced that starter but when i installed the new one, the continuous starter issue began. It would not stop cranking! I took out that starter thinking there was something wrong with it so i got it tested at auto zone, came back fine. I installed it again and no more starter issues! After a while i kept on hearing this awful grinding noise. I investigated it more and noticed that the starter had the wrong number of teeth for my flywheel. I got a new starter but the same issue occurred again with the continuous cranking.

If the switch tests okay, think about this:

It seems that after the first new starter was installed, tested and appeared to not disengage, was tested several more times and still wouldn't disengage, then it was finally exchanged for one with the correct pinion gear.

While or before installing the final/correct starter, did you have a chance to roll the engine and inspect the ring gear?

It's possible that attempting to use that first replacement starter (the one with the wrong pinion) - even those few times - may have damaged the teeth on the ring gear. And now, even with the correct starter installed, the Bendix can't disengage the pinion from the damaged ring gear. Another possible cause for a pinion failing to disengage from the ring gear is improper alignment of the starter.

To inspect the ring gear:

Pull the starter and, while barring the engine over, inspect the teeth on the ring gear one by one. You might find an individual tooth, or groups of several teeth in a row, that have been damaged.

If the leading edges of the gear teeth are deformed, the pinion gear will have trouble engaging the ring gear. And, if the trailing faces are banged up the Bendix will have trouble disengaging the pinion when the solenoid is de-energized.

If this is the case; it sucks, but it's not the end of the world. The ring gear teeth can be dressed up with the engine still in place using a file.

If, after inspection, you find only a few teeth (or one group) that need to be dressed - this can be done through the starter mounting hole.

But if you find that several groups of teeth (or nearly all of them) have been damaged, it is easier to pull the strut rods and drop the T/C splash shield. With the splash guard out of the way, you will have easy access to large sections of the ring gear. This extra step will actually save time in the long run.

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Use a 3-square (triangular) file to reform the teeth back to their original profiles. Do both the leading and trailing sides of each tooth. Also run a file across the teeth (parallel to the flexplate/flywheel) this will smooth out any burrs from the front faces - so they are flush with the ring.

While you are inspecting the ring gear, take a look at the pinion gear. Even though the starter is brand new, the pinion may have already been damaged from the ring gear.


If the ring gear looks okay, you can try shimming the starter. However, I have always been lucky and never had to use any shims, so I can't offer any help on how to do that.
 
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chengny

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Have you verified that two terminals on the starter are not making contact?

He means are the terminals of any of the three red leads that go to the big stud making contact with the purple wire on the little stud:

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Hey guys its been a hectic week! I just finished up a semester of school and had to deal with finals while packing and moving out of my apartment so i literally had no time. Jerry and yevgenievich i really do appreciate you guys trying to help me out.

Two new issues came up. I don't think the starter is getting caught on the fly wheel because I went under to check my flywheel like you had described and it is completely chewed up. I am still shocked that it started all those times. Theres this one sections where its missing all its teeth! I'm gonna need a new flywheel. Also the two terminals on the starter are not making contact, i made sure of that.

I was desperate and really needed to move my truck so i got all my buddies to help push my truck to bump start it down the hill. I have the ignition switch in the ON position, just one position before the starter will crank. I pop the clutch and the motor purrs as usual... however my problems don't end there, i put the car in neutral and not even a few seconds after the rpms wind down and the motor dies. I let it roll down the hill a little more and try to bump start it again. This time i constantly have my foot on the throttle giving it gas. That seemed to do the trick but as soon as i let my foot off the gas it wants to die. What is the problem now?!?! AGHH It seems like i can't catch a break with this thing. I fix one thing, and another breaks. What could it be this time?
 

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