LS 400 Horn

[ted55]

Good morning all, My horn has stopped working apparently it has something to do with the air bag,my interior is beige,I’m having trouble getting a match,i would be grateful for any advice.kind regards Ted 55 happy Father’s Day 😁

[Malc1]

Ted hi good morning 

There’s a few others here with a Mk4 Ls400 and I’m sure someone will be able to offer some useful advice shortly 

Good luck

Malc 

 

[Tel]

Post in the LS Forum & you will get far more responses.

Tel

[ted55]

Thanks Malc for your reply kind regards ted

[steve2006]

Hi Ted, hope you are well.
 

Unfortunately I sold my year 2000 LS400 electrical manual to another member but cannot now remember who it was.

It is very unlikely to be the airbag itself, from what I recall there is an earth wire to the steering wheel centre metal frame ( black wire I think) which is riveted to it, this rivet becomes loose so no longer earths when the pad is pressed.

There is also a 10A horn fuse and a horn relay involved. What you could do to eliminate theses components is get in the car, close the door and then lock the car with the remote. Then open the door which should activate the alarm sounding the horns confirming this section is working.

You could just fit a separate switch for the horn somewhere convenient bypassing the horn pad if this is the cause of the problem.

If you are really stuck you’re welcome to drive down to me just over the county border.

 

[ted55]

Hi Steve great to hear from you thank you for the information, i would love to drive down to see you,kind regards ted

[steve2006]

Ted’s horn is now working again 😀

Initial diagnosis suggested a defective clock spring as there was no earth path present when the horn pad was pressed so it was decided to fit a separate horn push switch.

However while reassembling the column shroud I noticed a broken black and silver wire between the moveable part ( tilt and telescope section) and the fixed part of the steering column.

Turns out this is the earth connection between the 2 parts and many years of movement had caused this wire to break out of the crimped connection.

Reconnecting this wire restored full horn operation as the earth path was now present again.

The first photograph shows the crimp connector and the wire circled and the second the earth wire on the exploded parts diagram.

[Malc1]

Excellent Outcome

Well Done

Malc

[ted55]

Thank you Steve for your expertise in dealing with my horn issue ,it was great to see you, thanks again see you soon 😁