AC lit up but not working, Eco Engine Off is, err, off - short between the two?

[NickRG]

Hi all, 

recently acquired a 1.33 09 IQ. Always been a fan, its a cool little car and a great drive, but mine is suffering a little. The AC unit doesn't work (I knew this when I got it). Its lit up, but with just a blank screen. No fans, no air... no nothing. Tried the AC panel diagnosis following another post on here, but no change. The Eco engine off suffers a similar oddity and the ECO light is constantly flashing. The controller knows when it should turn the engine off (the Eco-Off dash light comes on when stopped and out of gear), it just doesn't actually turn the engine off  aaaaand the dash is not rear-lit (guessing the bulb behind the speedo has gone). 

Initial code scan in the garage - one code in the system linked to stop start and AC unit apparently - potentially indicating a short circuit somewhere between the two - seems like a very specific code and potentially a wiring fault :(. I suppose this may somehow have blown the dashboard LED, although I always thought those were pretty robust.

 

Just wondering if anyone has ever had anything similar happen? Or any ideas as to what it might be? 

Have tried:

• Checking the fuses...
• Replacing the AC control unit (picked up a working spare from a scrapyard before trying the garage)...
• Driving it for long enough to make sure the Battery is charged (figured it may have been left idle for a while)
• Pushing the eco-off button to check it wasn't simply turned off (simple fixes first) 
• Poking it with a stick
• Staring at it really hard for a while

 

Any advice/ideas gratefully received. It goes back to the garage next Thursday, but anything I can try to minimise the amount of time it spends there would be ace - they're not a common car and they're not a common car to fail, so I expect the garage may need some time with it. 

 

Regards

 

Nick 

 

[FROSTYBALLS]

What is the code?

[NickRG]

Good question

Its U0164 - in my notes it says "comms with A/C control unit open circuit or disruption"

 

[davidgilmour]

On 7/6/2017 at 3:32 PM, NickRG said:

Hi all, 

• Poking it with a stick
• Staring at it really hard for a while

 

 

 

Try staring at it while poking it with a stick :-)

seriously, lots of AC breakdowns in the IQ here recently and on the German forum too.

[Vscudetto]

What other codes are stored in the system? May indicate communication error between several systems. If nothing else then most likely the AC controller unit is at fault. Is the Battery original/genuine and for stop/start?

[NickRG]

So there weren't any other codes in the system, it was just that one. I'm assuming you mean the chip that controls the AC (not the v shaped control panel on the dash, which has already been swapped and checked).  Any idea if the chip is specific to the 1.33 IQ3? There's a few on eBay for £30 for the A/C on the 1.0 litre IQ2s which I imagine would be the same. Just be good to know if the garage come back with the same answer and I can then get the part from a breaker and avoid paying too much for a new one (although, tbh, no idea what they cost new). 

Not sure if the Battery is original or genuine, its a GS Yuasa Q-55R. Says its "For stop-start" so assume its at least unlikely to be the right type (although possible that the Battery is worn etc). Can probably ask the garage to check the output and make sure its not something simple like that for the rough idling/eco-off issues. 

(ps. thanks for the thoughts! been a while since I car tinkered, and its good to get a few views on what might be going on)

@davidgilmour - I can now also add staring at it while poking with a stick. No joy, but my neighbor now looks at me a bit funny. ;)

 

 

[davidgilmour]

On 7/10/2017 at 0:55 AM, NickRG said:

 

@davidgilmour - I can now also add staring at it while poking with a stick. No joy, but my neighbor now looks at me a bit funny. ;)

 

 

Ask this guy to help you, he is a real pro!

Put your iPad in the IQ and play this video with the front of the iPad facing towards your broken AC

 

[NickRG]

Wow. 

What a man. 

IQ now fixed and running - the garage replaced the A/C controller/amplifier unit with a part from a breakers yard (good shout @Vscudetto - it was indeed that part at fault). Few niggling problems in the a/c after it was all up and running (sensor seems a bit dodgy) but a regass, a drive, and a quick blast on hot/cold seemed to sort it out.

The stop-start now also works, I believe because the engine-off function knows the status of the a/c unit (one of the conditions for it being able to turn the engine off). 

Thanks for suggests all. Especially Braco the gazer. Have one more small problem with the IQ (cluster panel lighting), which I'll start another topic on, but until then, I'll leave my Ipad with Braco staring at the instrument cluster to see what happens.