Air con not working right? Replace the V68 motor - HOW TO.

Chat about your 9n Polo (inc GT and Fun)
littlepolo
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Re: Air con not working right? Replace the V68 motor - HOW TO.

Post by littlepolo »

Surgery complete.

One thing to note is the connector assembly and pot can be lifted out together (see photos). I only discovered this after leveraging out the pot on the old motor. I used a marker pen to indicate the position of the gear on the original casing and ensured it was realigned on assembly with the new parts.
IMG_20190722_080846.jpg
IMG_20190722_081158.jpg
IMG_20190722_081520.jpg
Reconnected the plug before reinstalling and checked operation. It appears the motor only goes from cold to open and nothing in between (at least I cannot hear it move in between those extremes). Is any kind of calibration needed?

Replaced the original large bracket without too much difficulty (the new one was not suitable at all).
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alexperkins
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Re: Air con not working right? Replace the V68 motor - HOW TO.

Post by alexperkins »

Thats right. The air system on these is a bit of a strange beast
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Re: Air con not working right? Replace the V68 motor - HOW TO.

Post by RUM4MO »

You will need to "calibrate" it within the AC controller by performing "basic settings" using VCDS or similar, doing that lets the AC controller know where the mechanical endstops for that flap are, so it drives the motor to each end, ie until it detects no further change in the voltage on the feedback potentiometer, logs it as one end stop, then drives in the other direction, then logs the other endstop. From then on, the furthest it will command that flap motor to move is between these two endstop limits.
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alexperkins
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Re: Air con not working right? Replace the V68 motor - HOW TO.

Post by alexperkins »

Just noticed i totally bypassed the calibration questions lololol i blame lack of sleep
littlepolo
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Re: Air con not working right? Replace the V68 motor - HOW TO.

Post by littlepolo »

Do I need the full version of VCDS to do this?
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alexperkins
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Re: Air con not working right? Replace the V68 motor - HOW TO.

Post by alexperkins »

No, free is sufficient. Basic settings on the appropriate group under Auto HVAC
JohnJT
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Re: Air con not working right? Replace the V68 motor - HOW TO.

Post by JohnJT »

Just created an account to post on here and say a massive thank you for this thread, I’ve got a Rapid Spaceback so not quite a Polo but had the same problem.
Couldn’t find anything anywhere about it, and any garage I went to said it was a full dash removal job and were talking £££££.

Managed to sort it out myself within an hour tonight, and after a year or so of playing the temperature roulette game I finally have fully selectable temperature again :lol:
littlepolo
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Re: Air con not working right? Replace the V68 motor - HOW TO.

Post by littlepolo »

I did basic settings and heard the motor moving as it went through the process.

It was hot today so I put the air con on, but no cold air. The air con sounded like it was working and it had been working recently.
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Re: Air con not working right? Replace the V68 motor - HOW TO.

Post by RUM4MO »

Bother, next thing might be a recharge of R134A.
littlepolo
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Re: Air con not working right? Replace the V68 motor - HOW TO.

Post by littlepolo »

Would one of those kits from a high street retailer do the job?
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Re: Air con not working right? Replace the V68 motor - HOW TO.

Post by RUM4MO »

Difficult to say, it will depend on how short in charge weight the system is, plus I think that some proper AC places or a mobile AC person might only charge the same to recover, weigh, vacuum, refilling that system.
littlepolo
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Re: Air con not working right? Replace the V68 motor - HOW TO.

Post by littlepolo »

Before going ahead with a regas/air con service I checked the data and found:

3 faults found:

01596 - Motor for Outside/Recirculated Air Flap (V154)
30-10 - Open or Short to Plus - Intermittent

01596 - Motor for Outside/Recirculated Air Flap (V154)
41-10 - Blocked or No Voltage - Intermittent

01596 - Motor for Outside/Recirculated Air Flap (V154)
29-10 - Short to Ground - Intermittent

Cleared the codes (cannot recall if they were there before I replaced the V68)

Did basic settings again.

Engine off

Voltage 12.10V, Fresh Air Blower (V2) Position 0.0V, Coolant Fan (Stage 1) OFF, Coolant Fan (Stage 2) OFF

Compressor Load 0.0%, Refrigerant Pressure (G65) 4.20 bar, Compressor Shut-Off 6.0, Temperature (G263 Evaporator) 20.0C

Engine on

Voltage 13.80V, Fresh Air Blower (V2) Position 6.50V, Coolant Fan (Stage 1) OFF, Coolant Fan (Stage 2) OFF

Compressor Load 82%, Refrigerant Pressure (G65) 5.0 bar, Compressor Shut-Off 0.0, Temperature (G263 Evaporator) 20.0C

Still no cold air.
littlepolo
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Re: Air con not working right? Replace the V68 motor - HOW TO.

Post by littlepolo »

Just checked for operation of the AC fan when the AC is running. No rotation.

Also had a recurrence of the following fault:

01596 - Motor for Outside/Recirculated Air Flap (V154)
410-10 Blocked or No Voltage - Intermittent.

Edit:

Cleared the code and it has not yet returned.

Fans spin up on the output test.
littlepolo
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Re: Air con not working right? Replace the V68 motor - HOW TO.

Post by littlepolo »

Correction. Fans spin up initially on the output test but run for just a few seconds before stopping. The test does not proceed.

I've Googled and found this is symptomatic of fan resistor pack problems. That's one avenue to investigate.
littlepolo
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Re: Air con not working right? Replace the V68 motor - HOW TO.

Post by littlepolo »

I could not find any info on what the correct gas pressures should be for the Polo, but did find the attached chart which is generic for R134a.
R134a pressure chart.png
On this basis, the 4.2 and 5.0 Bar (engine off/on) I measured is low for the high side.

Going to book in with an AC specialist
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