How does the steering wheel get grounded? The ground connection for my horn membrane switch has a very high resistance to ground. Even the steering wheel shaft does not appear to be a solid ground. Is there a ground circuit in the clock spring assembly for the horn membrane to receive a ground?

 

I believe the black wire grounds via the steering wheel frame itself under the bolt

 

Yes, that's true, the membrane gets ground from the steering wheel. However my steering wheel isn't grounded. The steering shaft isn't grounded where the steering wheel attaches.

Removed wheel, clock spring assy and both stalks for turn signals/headlights/ etc. All the metalic surfaces are grounded including the steering shaft where it overlaps/ meshes with the next shaft going forward ( telescoping wheel). However, after the u-joint for tilt function I loose the ground.

With ohmeter connected between batt ground bolt and steering shaft where steering wheel attaches, if steering wheel is moved even the slightest, the resistance jumps around. From 800 ohms to over 1M ohms.

The plate for the steering locking pin engagement was removed when I bought the car ( recall?) but horn has been working ok for 10+ years.

 

That's interesting.

As part of my swap to a C6 steering wheel, I investigated the steering wheel's ground.
On my car the upper steering wheel shaft (which has splines that the SW sits on) is grounded, therefore the SW itself is. There are ball bearings between the upper steering shaft and column, so it stands to reason that the whole steering column is grounded to the car. And the steering column is bolted to the chassis which I'm assuming is steel at that attachment point.

 

There's a plastic piece that connects the horn relay coil to the membrane. Can't figure out how to remove it. I was able to probe the upper shaft to column bearing. The ***** are grounded but the steering shaft isn't. Wierd. Wonder if someone used dielectric grease to lube it?

 

Steering column.

 

Well that is very weird.
The inner race which the ***** run on is part of the upper shaft's geometry. And there is a preload spring forcing the ***** and upper shaft to make contact. So even if dielectric grease was used as a bearing lubricant, I'd still expect some continuity between the ***** and upper shaft.

There's no play in the upper shaft, right? I'm assuming that preload spring is still in place, which should be true if the upper shaft has no play.

 

Spring is there and zero slop in the shaft.

Wish I could disassemble the tilt portion further but it doesn't look too friendly.
Do you know how the round plastic gizmo (that one of the membrane wires connects to) can be removed? I'd like to get better access to this bearing.


Plastic gizmo

 

The first post in this thread shows C5 steering column disassembly, I think it will help answer your question.
https://www.corvetteforum.com/forums...in-c5-z06.html

 

Thanks for the link! Looks like a special tool is needed to expose the clip holding the plastic gizmo (turn signal cancel cam) on the shaft.

Found a decent breakdown on the steering column. It shows, for the 2000-2002 models at least, there's a "Inner Race"(14) and a "Upper Bearing Inner Race Seat" (13). Wonder if there's some corrosion or something between them and the steering shaft??

Appears the "u-joint" that allows for tilt is actually some plastic or rubber material (#28). If that's so, that would explain why I can't get a ground from the steering box.



2000-2002

 

There are 2 bearings on the upper shaft, I had forgotten that (14) inner race for the outboard bearing is a separate piece. But the inboard bearing's inner race is built into the upper shaft as seen below:



So the ground should minimally go through the inboard bearing. As you mentioned the plastic "U-joint" will surely insulate a ground connection at that end.

I have another post that goes into more detail on the main steering column wiring harness (underneath the column), particularly on grounding and horn wiring that might help. Post here: https://www.corvetteforum.com/forums...post1605330625
Here's an excerpt from that post: There's also a thicker black wire which provides a ground to the steering shaft and thus the steering wheel. So the steering wheel frame is grounded to the car

For convenience the picture below is from that thread and shows the wiring harness I'm talking about. Note that the separated black wire is the smaller black wire used for the horn.

I'm wondering if it would be worth probing the thicker black wire in this wiring harness and verify it's grounded and also makes connection to the steering column.

 

I'm assuming the small dia black wire connects to the slip-ring via the spring loaded contact coming out of the turn signal cluster. I get a stable 12V to the slip ring via the horn relay coil so I think that wire is good.

Got a tool ordered to help remove the retaining ring so I can remove the plastic slip-ring.

From the pic shown in the latest link, I can see I'm missing the black plate which I believe is the ring the steering locking pin engages. Wondering if the missing plate is adversely effecting the bearing pre-load and possibly the ground path?

I do get some continuity to ground thru the upper steering shaft, but it's unstable and varies considerably. Everything else metallic on the steering column has a stable, low resistance path to ground. Car gets driven almost daily so it's currently all back together. Special tool should be here Friday so I'll dig some more this weekend. Got a state inspection coming up at the end of this month.

 

Correct, and it's good you're seeing 12V there.

Interesting thought, I can't really answer. But this kinda goes back to my question about play in the upper steering shaft; I'm inclined to think that preload should be adequate if you don't detect any play in the steering wheel.

Curious, have you noticed if it varies consistently? For example, is resistance the same every time the steering wheel sits @ 3 o'clock ?

It's conceivable there's pitting and/or corrosion on the bearing *****, bearing races, etc. causing this issue... though I feel like if it were bad enough to affect continuity you might feel grittiness while turning the steering wheel. Maybe once it's apart you could spray electrical contact cleaner on the bearing(s) and see if that does anything for continuity. Then re-grease the bearing(s), of course.

Regardless, I'm glad you have the lock plate removal tool on order so you can investigate further. For whatever it's worth I used this one on Amazon, though had to bend the prongs inward to suit the C5's smaller-diameter lock plate.

 

I believe the inner and outer bearings are both in the same housing and that housing is definately grounded, so yeah, you would think at least one of them would give the steering shaft a solid ground.

I initially dismissed the locking ring being removed, but now I'm wondering if maybe I should try adding a washer to the stack-up to regain the orig spring press?? I'm assuming the locking ring went between the plastic slip-ring gizmo and the retainer clip. My parts breakdown, interestingly enough, doesn't show it at all.

Steering is smooth as butter. Can't see the inner bearing yet but the outer bearing seems to have sufficient grease. Doubt the bearing ***** are rusted/pitted, but I'll know for sure soon. It was a Florida car originally, but haven't found anything corroded yet (over abt 15 years).

The tool I ordered (Amazon) looks exactly like the one you posted, but a different brand.

Edit: In regards to resistance readings while turning steering wheel; i havent turned the steering shaft more than a couple of degrees maybe since I removed the clickspring.

 

Got the special bearing-spring compression-tool yesterday and jumped right in. There seems to be plenty of spring tension on the bearings without the steering lock-plate present. Was going to take the steering column completely apart but didn't have the right allen-head screw available to remove the tilt bushings.

Discovered this after I had already removed the large tilt spring. Thought it was going to be a bear to re-install, but I got the far end of the spring on it's nub then manhandled the close end of the spring (with the plastic guide) onto it's nub, then pushed the middle of the spring into place with my palm. I was paranoid I might get pinched so I placed a rag in between my hand and the spring. Popped right in. Whew,,, I was sweating that one.

Did take the outer bearing out and cleaned everything up. It comes out one-ball-at-a-time by flexing the plastic bearing separator (cage), then pop out the plastic cage with a small screwdriver. Pay attention how the cage comes out. One side is bigger than the other. A small magnet makes dealing with the ***** much easier.

Soaked the bearings in mineral spirits while I cleaned the race area with just a paper towel and just a tiny bit of mineral spirits. Didn't see any pitting/corrosion/oxidation anywhere.

Put it back together dry. Steering shaft resistance to ground now under 1 ohm and stable. Took it back apart and added grease (Mystic #2). Reassembled and still under 1ohm. Horn working consistently so far. I can only conclude the old grease was insulating the steering shaft.

Would have liked to cleaned/lubed the inner bearing too but if the steering shaft remains grounded via the upper bearing clean/lube, think I'll leave it alone.

 

Glad to hear the problem seems to be resolved for now! Hope it stays that way...
Appreciate the follow-up.

 

Thx for the help. Much appreciated.