Horn, Cruise and Air Bags Are Not Functional [SOLVED]

[Chaldaean]

Two years ago, I replaced the "clock spring" (spiral cable84306-33020) in the steering wheel, but that didn't solve the issue. I've also removed/cleaned all the associated grounding locations. The air-bag trouble light is on and neither the cruise nor the horn are responsive.

Assuming all three (horn/cruise/air-bags) issues have a common cause, I figure the next step is to trace the horn as that seems like the simplest circuit. I can run a jumper wire to ground the horn (simulating a press of the steering wheel horn pad switch) and the horn relay and horn itself works fine.

I cannot get continuity between the "EA1" connector and the steering wheel. In the wiring diagram it doesn't look like there is another connector between EA1 and the steering wheel. Maybe there is a broken wire somewhere.

Does anyone know of a location to focus on that would include the horn/cruise/air-bags? My next step is to pull the entire dashboard out, but I'm not sure if that's the right move.

I've included the diagram for the horn below.

 

[subzali]

Why did you replace the clock spring? Was it the first attempt to solve this or did it cause it?

 

[Chaldaean]

Why did you replace the clock spring? Was it the first attempt to solve this or did it cause it?

I replaced the clock spring as an attempt to solve the issue. The clock spring carries all three of the signals to the steering wheel. Thanks for the clarification.

 

[girupb]

My guess is that your replacement clock spring is no good. I’d check the clock spring’s continuity before running too far down any other rabbit holes.

 

[subzali]

But that would make two bad clock springs. The original and the replacement. But I agree that really is what those three circuits have in common, at least at first blush.

 

[2fpower]

I would think it is clockspring too. Can you take off connection from clockspring and see if depressing the horn gives you continutity?

If I recall, the clockspring is the same in a Camry about the same vintage. I picked up several for next to nothing from a local pick n pull. just remember to bring the torx tool and steering wheel socket.

 

[girupb]

But that would make two bad clock springs. The original and the replacement. But I agree that really is what those three circuits have in common, at least at first blush.

It would but..... it seems most likely.

I bought a used one and just rotated it gently all the way each direction and split the difference and installed with the wheels straight.

It’s easy enough to check it though.

 

[Chaldaean]

My guess is that your replacement clock spring is no good...

...I agree that really is what those three circuits have in common...

I would think it is clockspring too...

You guys rule.

I removed the brand new Toyota OEM clock spring (spiral cable) and started continuity testing. I started wondering how the cable could control the horn and multiple functions of cruise (on, off, accel, decel, cancel) with only two contacts. I Googled P/N 84306-33020, looked at some images and saw that there should be six contacts; not two.

So, I was sent an incompatible clock spring. I ordered it from amayama.com and it shipped from UAE. I have ordered stuff from that site in the past (typically half of US dealer costs) without issue.

I bought another clock spring (this time P/N 84306-28020; superseding) used on eBay for $40. Installed it, cleared the SRS code, cleared the cruise code and all was fixed!

Here are some images of the two clock springs and the order from amayama.com

Left = The "wrong" part. I still don't know what part number this is; the barcode doesn't seem to reference anything useful.

Right = The "right" part from eBay.

Notice the number of contacts and the thickness of the whole assembly (wider ribbon cable).

Thanks, again, guys. Stoked to put this problem in the rear view mirror.

 

[subzali]

Wow, good find! In hindsight it seems so simple. Maybe should have caught it when you said "3 signals" to the steering wheel. The cruise alone has 3 or 4, so that should have been a tipoff if we could have connected it to your replacement clockspring only having two pins. Glad you found the source of the issue!

 

[Desert Dino]

What did Amayama had to say about this? Are you going to send it back?

 

[Chaldaean]

What did Amayama had to say about this? Are you going to send it back?

Amayama won't send a correct replacement since I didn't have the part installed by a certified Toyota dealer and since it's been two years. They offered me a 20% discount on a new one, but I already bought a used replacement on eBay.

 

[Gbergma1]

Curious how did you reset the airbag light?

 

[Chaldaean]

Curious how did you reset the airbag light?

I followed the directions in the paper FSM, but I believe this is the correct sequence (link below). It took a couple of tries to get the timing. In the end, I used a stopwatch to gauge the seconds and got it right away.

Air Bag warning lights will not reset

 

[Gbergma1]

Thank you. I am on my 2nd try at a "cheap" clock spring, the first one was from eBay and it wasn't even close to fitting. The second one isn't OEM either, but the photo looked like a match. This part is on my beater truck, my wife gets to drive the nice one, which only gets OEM.

 

[HJ61alex]

UP/Update

My cruise control is over and my airbag light is on for about 10 years on my 95 1HDFT but my horn still work fine...

I 've test the clock spring and i think the continuities are ok, as for the 3 wires of the cruise and the yellow wire of the airbag, but i'm not sure.

I have a odb 41 error code, i've changed the throttle position sensor with no success (other thead )

The 84306-28020 have been replaced by 84306-33020 which has been replaced by 84306-24010 can you confirm?

The problem is that nobody can confirm that the new ones have 2 or 6 pins! (amayama or partsouq)


I've also orderer a 18 dollars chinese one which has nothing to do with the 84306-33020!

Any Ideas are welcome except going to toyota dealer (they ask 370 euros here for the clock spring!)