Horn relay

[Hal]

Good afternoon

will someone kindly tell me where is exactly the horn relay in 2017 Evora please?

I had to use my horn yesterday, snd it stuck ‘on’! Then after half a minute, it stopped but there is a lot of noise coming from the passenger (lhd..)foot well. And the horn is being activated in small stabs.

itried pulling each visible relay, but could not stop the noise! I pulled fuse C1 and this stopped the noise, but I am worried that I cannot find the relay.

thanks!

[Hal]

Trying to do some self help on the problem, it could be more complicated and expensive than I first thought. Certainly it needs specialist attention

it seems to me that there is not a relay for the horn - fuse C1 feeds A12 of the ICM and A11 of the ICM feeds the horn. ie the ICM acts as the relay. Maybe someone can confirm this and tell me why?

If this is the situation, and the ICM is a sealed unit, then I anticipate a large expense due to an otherwise small issue.

I would appreciate some general words on the ICM - why and what etc….and likely cost!

[Bibs]

This isn't something I've heard of before and there are no previous topics on it. I'll give the tech's at the factory a call and see if they can help too. 

[Hal]

Thanks so much Bibs - most kind of you.

looking again last tight, the noise, which sounds like a fast vibration, ‘feels’ as if it is in the ICM that is sending very short bursts of power to the horn. Horn button appears not to be stuck and operates as normal when pressed.

removal of fuse C1 stops the noise but of course I have no horn. Everything else electrical appears fine!

[Hal]

Bibs, woul

d you also ask the techies please, if the ICM must be replaced by a dealer or would I be allowed to make the change?

explain to them that I am way south of Toulouse and since Lotus sacked the Dealer in Toulouse,  my nearest is now 300kms away!

[DH2]

Have you tried remove the vehicle battery for a short period?  Worth a try in case it "resets" the ICM.

[Hal]

I did not remove the battery, but I left the negative disconnected over night so no power. It did not change anything.

I hope co-incidental, but last week my battery was dhowing signs of a failing cell . I took the opportunity to clean up the acid vapour dust residue and replaced it with an AGM type…

[Bibs]

FYI, the ICM doens't need to be programmed and is a straight swap. 

Before this though, some diagnostics will help. The ICM is a simple control module - signal in/signal out. If it's buzzing, it sounds like it's getting a signal and this could be from a short or dodgy connection from the horn wiring. The first thing to do would be to make sure you don't put the key in the ignition (or you could end up with a dreaded airbag light - dealer reset only), them remove the steering column shroud. You'll see the horn connector and wiring (a ribbon) - check this to make sure it's in good condition and the connector is seated correctly. 

[Hal]

Thanks Bibs - yes good advice and makes sense. I use the horn so little, and for this to happen immediately after a short beep is co-incidental, so will do a good check over the weekend.

Airbag light is already on and has been for a while. Does the ICM control this too?

[Bibs]

No, but it's a dealer reset via the Lotus Tech Centre only. To stop it it reappearing in the future, give the car a good 30 mins after keying off before you disconnect the battery, that's the usual cause of it. 

[exeterjeep]

re the SRS light...although this may be different for earlier/later cars??

https://www.thelotusforums.com/forums/topic/107363-airbag-light-on/

 

[Hal]

Thanks again Bibs! I have learned something today. Certainly last week i did not allow any time before disconnection.

[Hal]

To close this one off - yes, a loose connection. All my own fault as I used the horn wire to power a small accessory, and did not snap the connector shut properly....