Legacy7770

1.0 ecoboost ac cluch not engaging

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Hello everyone hopefully someone can help me out with this problem. 

My ac cluch is not engaging I'm not getting 12volts at the cluch. Can't seem to find out any information about where the ac cluch relay is.  Ac button and recirculation light up. Can someone please let me know where the ac relay is and any fuses on the circuit as I haven't a fuse box diagram. 

Yours sincerely Steve Evans 

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Since (at least) 2007 the focus doesn't have an AC clutch, most cars by 2005 moved to a far more efficient variable drive compressor.  The drive belt is attached to a cush drive that looks a bit like the old electromechanical clutches.

Variable drive compressors are linked to engine management systems... with benefits along the lines of reduced load during acceleration or large throttle application, reducing the load in colder weather, at idle etc.

All AC systems should be left on at all times.  Turning it off saves virtually NO petrol and doesn't improve performance (due to variable load compressors), but with it off, it wreck the compressor seals, lose gas and go wrong ,which will cost many thousands to fix vs the additional running costs of about £3 of petrol when leaving it on.  You also lose the safety benefits of seeing where you are going in the rain etc.

What you may be experiencing is the cold weather shutoff protection.  EVERY car AC system will shut off below 3C to reduce the risk of evaporator freezing (due to wind chill). 

You often don't notice

1) due to variable drive compressors - you haven't heard a massive clunk on most cars since the 90's

2) in low ambient temperatures water seldom stays in the air, so windows don't often steam up with outdoor temp below 3C (although this winter has been a bit odd and it has happened a bit more than normal)

 

 

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mines not working as its cold outside, but if you want to check for 12 v with connector off, bridge relay r11 switched side pin 3 and 5 . also check fuse 27 15a ( relay switch feed) and fuse 23 5a ( relay coil feed)

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Thanks guys so it's a variable compressor

On the 1.0 ecoboost. 

Does anyone know the correct pressure on both the low and high side of the system??

Can I jump the compressor cluch at the relay with the engine running  to check the pressure with the cluch engaged??

Yours sincerely Steve Evans 

 

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developed in 1985, fitted to the golf from 2003

 

 

 

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3 hours ago, Legacy7770 said:

Thanks guys so it's a variable compressor

On the 1.0 ecoboost. 

Does anyone know the correct pressure on both the low and high side of the system??

Can I jump the compressor cluch at the relay with the engine running  to check the pressure with the cluch engaged??

Yours sincerely Steve Evans 

 

you can bridge the relay engine running but be aware if the pcm isnt commanding the cluch to engage, the coolant fan wont be commanded either. so only breifly bridge to visually see if the clutch engages.  

i assume there is sufficient refridgerant in the system? 

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5 hours ago, Botus said:

 

Thanks mate I'll do a pcm self check in the morning that should engage the clutch on the compressor. 

Pressure on the low and high side is 50psi with the engine off and the same with the engine running. 

Does the 1.0 ecoboost definitely have a variable cluch on the compressor??

Yours sincerely Steve Evans 

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Hi guys spent some time on the focus and here's what I've found so far. Checked fuse F23 all good  F27 blown replaced fuse. 

Disconnected plug from compressor jumped relay pins 3 and 5  and found battery voltage. Back probed the earth on the plug and found battery voltage  

So it looks like the power and earth to the compressor cluch are ok 

Replaced compressor plug jumped relay pins 3 and 5 and it blows F27. 

So I'm guessing it's a cluch problem 

Any help would be much appreciated Thanks Steve 

 

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sound like clutch field coil has a short, or the short bit of wire to it. either a new coil or compressor now.

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I think so to mate. I'm thinking of replacing just the clutch coil that way I won't have to have the system filled up again. 

Anyone know if the compressors are the same for Borth the M1DA AND M2DA??

Anyway thanks again for everyone's help 

Steve 

 

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i cant see them being any different.  i think its a visteon vs16 variable compressor. used on all the 1.0 ecoboosts . as you can see theres a control soleniod at the right end of compressor. thats what controls the pressure i believe via the pcm

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Thanks mate you're a star much appreciated Steve 

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Well found an hour today for my latest project!!! And it does indeed look like the ac cluch. Used my vantage pro removed the plug for the ac clutch hooked up to power and earth at the ac cluch plug then with my autel then performed a KOEO self test which turns the fan on engage the ac clutch and I get battery voltage when the fan runs as it should. So I jumped the clutch and it looks like it's sized. Removed the 8mm bolt pulled the front off give it a bit of a clean and it's starting to move. 

Going to remove the clutch tomorrow to see what's going on. 

Steve 

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