Evora Air conditioning failure

[hamza]

Nope. Just not blowing very cold. 

[Brendonian]

This ECU reset isn’t likely to help then. 

[DH2]

On 17/06/2023 at 15:41, cdco said:

caused the spanner to momentarily illuminate but not latch.

Spanner light with never "latch", it will only ever come on for 30 secs then go off again - it is for an electrical fault (code) that does not affect emissions/catalyst  In this case, probably a compressor speed error.  This behaviour is described in the owners handbook.

Dave

[LotuStuart]

11 hours ago, hamza said:

Nope. Just not blowing very cold. 

This is usually being low on gas.

 

I read this thread quite quickly, and don't know how the aircon compressor is driven, but I don't see anyone talking about belt slippage who then says they checked/adjusted the belt tension. 
Is that a possibility?

[DH2]

6 minutes ago, LotuStuart said:

I read this thread quite quickly, and don't know how the aircon compressor is driven, but I don't see anyone talking about belt slippage who then says they checked/adjusted the belt tension. 
Is that a possibility?

Auto tensioner on the V6.

[LotuStuart]

Ah that would make sense! Presumably those tensioners don’t have an early failure rate. But then would lotus update the firmware rather than install an upgraded/new tensioner.
as I say, I’ve never put my head in an Evora engine bay so ….. 

[cdco]

23 hours ago, hamza said:

Nope. Just not blowing very cold. 

For what it's costs if you have a dongle and the app, useful in general with an Evora , just do the reset it costs nowt and if it doesn't clear the problem then it's back to the list... 

[Bravo73]

@cdco, a generic ODB reader can’t connect to the a/c ECU so a reset won’t have any effect on it. 

[DH2]

I'm assuming it is compressor codes stored in EMS (since there is no AC ECU).  It is usually a compressor speed fault code - there was a firmware update to overcome it (on Exige).

Dave

[Brendonian]

That right. There was a firmware update for newer Evora models, but not older ones. Hence my LE needed regular resets. Think the problem was solved when I replaced the compressor, but can’t be entirely sure as I sold the car soon after. 

9 hours ago, Bravo73 said:

@cdco, a generic ODB reader can’t connect to the a/c ECU so a reset won’t have any effect on it. 

Generic reader can’t read the AC error codes, but can reset them 👍

[hamza]

I don't have any kind of OBD dongle/ reader or app I'm afraid.

Have often thought of buying one but never sure which one and I always have several cars I'd want to use it with so no one ever seems to fit the bill.

[Brendonian]

Any generic dongle should be fine. I use an app called EOBD Facile. They’re all pretty cheap, so I’d recommend just buying one rather than trying to find the perfect combination!

 As stated earlier, it won’t help your AC problem if your spanner light isn’t coming on. You probably need a regas. 

[Bravo73]

6 hours ago, Brendonian said:

Generic reader can’t read the AC error codes, but can reset them 👍

I am always happy to stand corrected. 🤗

Have you got a procedure for that, please? (In order ‘to share the wealth’). Is it a similar process to resetting the airbag light?

[Brendonian]

I’ve never had to reset an airbag light, and the procedure varies depending on which app you’re using, but there’s should be an option to clear all codes. That’s all that’s required 👍

[cdco]

17 hours ago, Bravo73 said:

@cdco, a generic ODB reader can’t connect to the a/c ECU so a reset won’t have any effect on it. 

Might not be able to read any ... Mine didn't BUT the OnLY thing I did was a read ... No codes .. a reset anyway and then I had chilled air ... So by practical experiment a complete reset command with respect to the unreadable ac codes (can't speak for other features) cleared them out ... Weird but true...

1 hour ago, Bravo73 said:

I am always happy to stand corrected. 🤗

Have you got a procedure for that, please? (In order ‘to share the wealth’). Is it a similar process to resetting the airbag light?

As @Brendonian said I just hit the "clear all codes" option in the "Car Scanner" app.

[Markindevon]

Don't know if this helps but my aircon experience was somewhat similar... Not blowing cold and the spanner would come on.  Dealer thought it was the compressor and so it was replaced (thankfully under warranty) and, after a few days the symptoms were identical...

Dealer then changed the serpentine belt and it's been perfect since!  Apparently they can slip, just a bit, and it upsets the ECU, which then shuts down the compressor to protect it etc...

[EGTE]

That was 2 new compressors, then!  But good info.

[hamza]

On 21/06/2023 at 14:11, Markindevon said:

Don't know if this helps but my aircon experience was somewhat similar... Not blowing cold and the spanner would come on.  Dealer thought it was the compressor and so it was replaced (thankfully under warranty) and, after a few days the symptoms were identical...

Dealer then changed the serpentine belt and it's been perfect since!  Apparently they can slip, just a bit, and it upsets the ECU, which then shuts down the compressor to protect it etc...

I think I may be experiencing this.

Car has been sat for a month while I was away (on trickle charge). Started it up yesterday and the yellow spanner comes on for a while after starting and then goes out. A/C doesn't seem to be working at all any more.

Took it for a short spin and whilst cruising at about 70mph the spanner came on briefly and then went out again too. I can't remember for sure but I might have been playing with the HVAC controls at the time (definitely not turning on/off a/c as that stays on permanently).

Any suggestions or is it time to book it in with someone to take a look?

[DH2]

Spanner light indicates there is a fault code stored for your delectation...

Dave

[hamza]

well I recently acquired a bluetooth OBD reader... guess this is a good a reason as any to try it out. 

Any recommendations on apps to use with it for the Evora?

[DH2]

Generic OBD may, or may not find it.  We have various specific OBD tools, Snap On, Autel, etc, so can't say for sure which software will work well.

Could try Torque?

[hamza]

Ok thanks. I'll it a go... else I guess time to call Lotus again