06 Golf V 1.4 petrol - EVAP Control / Purge Valve - Open Circuit - P0444

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Fri 14 May 2021 21:14
06 Golf V 1.4 petrol - EVAP Control / Purge Valve - Open Circuit - P0444 - Garp242

Hi All. Hoping someone will be able to help with a bit of a head-scratcher !!
I'm getting a code P0444 - EVAP Control System - Open Circuit.
I've done all the checks on the Purge Valve itself, and all seems to be working ok.
Continuity - OK
Resistance - 25 ohms
Audible click when connected to a 9v battery
No vacuum at idle when feed disconnected

But when I checked the voltage at the Purge Valve connector, it reads 3.9 volts - Should it be reading battery voltage ??

It triggers the Check Engine light, which when erased, comes back on when engine is started. There are no other fault codes present other than P0444.
I'm assuming this is going to be an MOT failure as it is related to Emissions.

Any help greatly appreciated ...

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Fri 14 May 2021 21:49
06 Golf V 1.4 petrol - EVAP Control / Purge Valve - Open Circuit - P0444 - Railroad.

Get yourself a noid lamp. Perfect for checking circuits such as this.

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Fri 14 May 2021 22:58
06 Golf V 1.4 petrol - EVAP Control / Purge Valve - Open Circuit - P0444 - Garp242

I've no idea what that is ???

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Fri 14 May 2021 23:43
06 Golf V 1.4 petrol - EVAP Control / Purge Valve - Open Circuit - P0444 - Rerepo

I know very little about this system but I am guessing the purge valve solenoid is duty-cycle controlled by the ECU. Therefore you will read less than 12V at the solenoid (voltage will vary according to duty cycle).

I suspect also that the solenoid has a positive feed and is switched to ground by the ECU. So check the supply voltage and also that the ECU is switChiNg to ground properly. An oscilloscope would be useful.

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Sat 15 May 2021 08:13
06 Golf V 1.4 petrol - EVAP Control / Purge Valve - Open Circuit - P0444 - jc2

A purge valve should only operate on a warmed-up engine and only at part-throttle then.ie.only when running on "closed-loop".

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Sat 15 May 2021 09:22
06 Golf V 1.4 petrol - EVAP Control / Purge Valve - Open Circuit - P0444 - elekie&a/c doctor
With engine running , there should be battery voltage on one of the pins, should be a blue/red colour wire . The other wire is the return signal to the engine ecu . As already suggested, this is a pulsed signal commanded by the ecu if all parameters are met .
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Sat 15 May 2021 09:43
06 Golf V 1.4 petrol - EVAP Control / Purge Valve - Open Circuit - P0444 - Garp242

When I tested this I am getting 3.9 v - both with ignition ON & with engine running. I guess that points to a problem in the wiring ??

Is this a job for a VW Dealership, or could a good Auto Tech sort it out ??

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Sat 15 May 2021 09:35
06 Golf V 1.4 petrol - EVAP Control / Purge Valve - Open Circuit - P0444 - Garp242

Thanks Elekie Doctor & Rerepo for you're replies and that information.

I'm not really up to scratch on auto electrics .. .I think maybe it's a job for someone with more experience and proper Diagnostic equipment.

I'm assuming since the fault code is Emissions related, that it would be an MOT failure ? Would it be an expensive fix ??

Edited by Garp242 on 15/05/2021 at 09:47

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Sat 15 May 2021 09:53
06 Golf V 1.4 petrol - EVAP Control / Purge Valve - Open Circuit - P0444 - elekie&a/c doctor
You need to load test the power supply wire with a bulb . The circuit is fused , so could be a bad connection at the fuse location. Could be one in the engine bay fuse box . Not sure which one , as there are so many different levels of fuse box fitted to these Golf models . Shouldn’t be too difficult for an auto tech to sort this out .
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Sat 15 May 2021 15:00
06 Golf V 1.4 petrol - EVAP Control / Purge Valve - Open Circuit - P0444 - Garp242
You need to load test the power supply wire with a bulb . The circuit is fused , so could be a bad connection at the fuse location. Could be one in the engine bay fuse box . Not sure which one , as there are so many different levels of fuse box fitted to these Golf models . Shouldn’t be too difficult for an auto tech to sort this out .

I dont have a Wiring Diagram for the car yet, but from info found on internet, there are a couple of fuses ( F9 & F24) that control N80 Valve. Should I expect the feed wire to have changed colour when it reaches the fuse box, or will it still be Blue/Red ??

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Sun 16 May 2021 15:08
06 Golf V 1.4 petrol - EVAP Control / Purge Valve - Open Circuit - P0444 - Garp242
You need to load test the power supply wire with a bulb . The circuit is fused , so could be a bad connection at the fuse location. Could be one in the engine bay fuse box . Not sure which one , as there are so many different levels of fuse box fitted to these Golf models . Shouldn’t be too difficult for an auto tech to sort this out .

Just an update on the Golf - Purge Valve - Open Circuit problem

After doing a bit of trawling on Google, I found out that it was either F23 or F24 in the engine bay, that controlled the feed to the Purge Solonoid (N80) ...

So I went out to have a quick look this morning. F23 seemed ok, but F24 was missing - power there but No fuse !! So I put a 10 Amp fuse in and Bingo, battery power at the feed connector ...

Erased the code and all seems good now ... Never discount the simple stuff, I suppose.

Many Thanks to you all for doing your bit to help.

Edited by Garp242 on 16/05/2021 at 15:21

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Sat 15 May 2021 14:28
06 Golf V 1.4 petrol - EVAP Control / Purge Valve - Open Circuit - P0444 - Railroad.

I've no idea what that is ???

It's a test lamp specially designed for checking fuel injection system wiring. They fit easily into the plugs that connect to the components of the system. There tutorials on YouTube that explain what to use them on and how to do it.

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Sat 15 May 2021 14:50
06 Golf V 1.4 petrol - EVAP Control / Purge Valve - Open Circuit - P0444 - Garp242

I've no idea what that is ???

It's a test lamp specially designed for checking fuel injection system wiring. They fit easily into the plugs that connect to the components of the system. There tutorials on YouTube that explain what to use them on and how to do it.

Oh Right. Thanks for that . I'll have a look.

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