Brakes

Alright folks, we're back!

This time, it's abs and brake lights, and hard pedal, as well as occasionally just the brake light and hard pedal.

If it happens while I'm driving, it takes several uses of the brakes to get the 'hard pedal' (as the accumulator still has some pressure?), and sometimes the brake light will illuminate and then just randomly go back out. Likewise, sometimes I'll get one or both lights and the hard pedal, and then they'll go out and the brakes return. Sometimes. Sometimes the lights stay on and the brakes stay hard. The abs light does not always come on, but the brake light and hard pedal are consistent symptoms. Also, the abs light doesn't always come on with the initial 'key on' system check. Just sometimes. If it wiggle or remove and reinsert the ignition switch, the problem usually subsides for a time.

I checked the fuses again, just to make sure, and they're all good. However, when I was putting the cover back on the fuse box in the driver footwell, I bumped the big wad of wires coming from the ignition switch, and the chime turned on momentarily. The door was open, but the keys weren't in the ignition. I haven't done anything with the 'key in door chime' wire that was hanging loose.

Just moments ago, after fiddling with ignition switch, which is brand new, I turned the car on, the system tested, the lights went out, and I had a nice brake. Then I shut it off, depressurized the system, and tried again, without touching anything. Lights stayed on and pedal was hard.

Am I wrong in believing that the underlying issue is electrical, in some way? Are there any other connectors between the ignition switch and the abs module that might be loose?
 
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>Am I wrong in believing that the underlying issue is electrical, in some way?

If messing with the harness has a 1/1 effect, then no.

>Are there any other connectors between the ignition switch and the abs module that might be loose?

Yes, tons. Check them via your EVTM, but again, if you can mess with the harness at one location, then the issue is most likely at/near that location.

Can you take a photo of the new installed switch that shows the connector surface where it meets the switch body?

Might need to warranty that new switch. The constant tension between the switch contacts and connector is such that I'd suspect even a small defect could raise heck.

BTW, how many miles on the key cylinder and steering column?
 
Vehicle and all components have 136--- miles. There were, up to 107--- miles (when I obtained the car), preventative maintenance, and some other things like suspension replacement (co Troy arms, I believe), radio and speakers replacement, and other stuff. To my knowledge via service records, neither of the two previous owners had anything done on the steering column, or key cylinder.

EVTM? :D ...I do have the shop manual, for what it's worth mentioning...

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Vehicle and all components have 136--- miles. There were, up to 107--- miles (when I obtained the car), preventative maintenance, and some other things like suspension replacement (co Troy arms, I believe), radio and speakers replacement, and other stuff. To my knowledge via service records, neither of the two previous owners had anything done on the steering column, or key cylinder.

EVTM? :D ...I do have the shop manual, for what it's worth mentioning...

View attachment 67330View attachment 67331View attachment 67332View attachment 67333View attachment 67334

Good evening


I would try the following to get the light(s) to go out.


- 1. Remove the steering column covers. Key Off. Loosen the 2 ignition switch set screws and re-adjust the ignition switch slight forward or backward depending on where you originally installed it. Tighten screws. Cycle ignition key On Engine Off. Does this fix the problem. If not Key Off. Look at the upper/lower section of the switch. Cycle Key On Engine Off. If you can see unusual movement/separation push up on the bottom section (the connector wires). Are/Is the light(s) out? If so the switch is bad.


- 2. Key Off. Open the hood. On the radiator support, driver side next to the headlight assembly there is a large ground circuit bus G-121 (5 wires attached), white in color. Remove the bus (10 mm green bolt). Clean the bus tab and the sounding radiator support of corrosion. Re-attach the bus. Cycle Key On Engine Off. Are/Is the light(s) off now?


As KMT stated a Electrical and Vacuum Troubleshooting Manual is a must for electrical troubleshooting.
 
Your pics of the ignition switch didn't show the side that I was wanting to see, so I highlighted the edge.

IMG_4601b.jpg

This edge is what loosens up. It should be tight and have no visible gap.
 
pics of the ignition switch didn't show the side that I was wanting to see

Me too...good pics otherwise, thanks.

But let's try this - find a long zip tie that will wrap around the switch/connector so you can clamp them together with authority - use two or three, perhaps. Then test.

I'd also treat the tabs inside to some connector grease - one or two in the middle on the connector look a bit corroded...see if you can clean them up without doing any damage, etc.
 
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So I just tested the system several times and it's good, after leaving the ignition switch unplugged all night. It does this. It could work for a week or for half a minute.

Anyway, here are some pics of the old switch and the new one. The new one seems to only have a gap large enough to MAYBE slip a piece of very thin paper (standard printer paper would be just too large) into it. I feel like it has a little dirt there that accentuates the gap, if there is one. The old switch had an obviously large gap.

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I found my safety posi bit that my sixteen month old son so lovingly stowed between the passenger seat and the center consul... he's learning how to work on cars, I guess.:cool:

So I was able to take off the new switch for some more pics. There doesn't seem to be any sort of gap, although warrantying the new switch really couldn't hurt at all. The other side doesn't have any gap whatsoever and is sitting very tight. This is the side that looks a little separated, if at all.

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When assembled in the car, as mentioned, can you see any movement/torquing/lifting/separating when you cycle the key on/off?

At this point, I'm stumped why you (still) have typical switch symptoms w/new switch, but nothing visual...

Is the key action at the cylinder sloppy? Can you remove the key with it still on?
 
So I got connector grease and put that on the connector and the copper tabs the connector plugs into. Ran fin for 20 minutes and then the lights came on. Made it home without the brake pedal getting hard using the gears to slow down, but it's hard as a rock now, and I'll have to unplug the switch and fiddle with the harness to make it work again. Probably.

There is very slight slop in the turning motion at the key cylinder, and also slight in/out slop, but I cannot remove the key unless the vehicle is off and I press that little white button and turn the key totally off. Y'all know what I'm talking about there.

Still baffled. I haven't looked at the g-121 circuit bus yet. I'll update when I do.
 
So I got connector grease and put that on the connector and the copper tabs the connector plugs into. Ran fin for 20 minutes and then the lights came on. Made it home without the brake pedal getting hard using the gears to slow down, but it's hard as a rock now, and I'll have to unplug the switch and fiddle with the harness to make it work again. Probably.

There is very slight slop in the turning motion at the key cylinder, and also slight in/out slop, but I cannot remove the key unless the vehicle is off and I press that little white button and turn the key totally off. Y'all know what I'm talking about there.

Still baffled. I haven't looked at the g-121 circuit bus yet. I'll update when I do.
The 5 speeds have that key release button so thats how its supposed to operate. You still might try rocking the key forward/backwards within its play range and see if that clears up the brake motor whenever it drops out again.

Oh.... and there is a wire clip thats supposed to help secure the connector to the switch body. I didn't see it in your pictures. For that matter though, I don't have it on mine because I was "confused" with how it attaches.. :D

Something else to try is to leave the steering column covers off and grab/pull/wiggle the harness while its running. Maybe theres a loose wire? I'd also not rule out something in the fuse box or other loose wiring in the circuit.. such as the power sides of the relay.

Sorry to say, but electrical problems are a "piece of round bread used for gyros" sometimes. (Someone explain how that term made it on the censored list) :rolleyes:
 
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Was just wondering. I'm totally lost in the evtm, so I'm just dinking around with the harness in that area and seeing what happens.
 
So I took the car by the best local mechanic (honest, good guys my Dad's gone to for years; two of them owned super coupes), cuz I need the AC to be fixed anyway. The word so far on the abs is that there's a reading from the test connector in the trunk that says 'permanent error'.

Thoughts?
 
They suggested taking it to the dealership for additional testing (testing the entire harness for continuity).

Would any of the fine people here have a spare abs module just happening to be randomly laying around?

Or, alternatively, a part number that I can search?
 
Good afternoon

Unless you are lucky and someone has past experiences with SC troubleshooting the dealer ship route will likely come to a disaster conclusion.

Do you still have both anti-lock and brake lights on? If so did the mechanic check for ground continuity with a EVTM specifically addressing anti-lock?

A quick visual way of troubleshooting the anti-lock module.

Disconnect the trunk package tray pin and pull down the corner at the driver side to get access to the anti-lock module. Be careful with pin as it will break without much effort.

Remove from the tray and inspect for any corrosion/damage/evidence of electrical overheat-leakage on both the module and electrical connector pins. Check the harness for any kinks/routing issues.

Smell the module. If the smell of burned electrical transformer is present the module is bad. If no defects found, apply die-electric grease and re-install. Power up and see if the light(s) goes out.
 
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