Galaxy mk1 2002 cooling fan and AC not working

[Terry Barnaby]

Hi I have an old Galaxy MK1 2.3i 2002 which although is running well, the engine cooling fan is not working (temperature gauge starts increasing if idling in a traffic jam) and the AC stopped working sometime in the last 4 months or so (it was working last summer).

The AC was refilled recently, but still doesn't work. The AC pump was not engaging and fan was not running. I put on an ODB fault code reader and showed the errors: P1474: FCLOW and P1479: FCHigh. So I suspect the fan control. I have a Haynes manual but the electrical circuit diagram for the fan operation looks nothing like on my model (There are a few variants in the Haynes manual). On looking around the car it has what looks like a Fan control module 7M5919506 under the battery fuse box near the battery in the engine compartment. Just in case the issue was this I purchased a second hand one. This did not make a difference (although that one could also be bad).

I had a look at the two layers of relays behind the fuse box under the steering in the drivers foot well (UK) but, without a circuit diagram I don't know which relay does what.

Any ideas where I can get an electrical circuit diagram that might match my car ?

Any ideas where to look for the problem ?

[TomsFocus]

Hi,

A 2002 Galaxy is too early for me unfortunately, no experience with them.  However, I do know they were heavily based on the VW Sharan.  The 2.3 petrol is a Ford engine though, so I'm unsure whether the fan system on this particular one will be Ford or VW.  It might be worth looking for some Sharan wiring diagrams to check.

Have you tried powering the fan directly with a 12v battery feed?  I wouldn't be surprised if the fan motor is worn out by this age.

[Terry Barnaby]

Thanks for the reply, yes its a mixture of Volkswagen and Ford. Not sure on the Fan system. Certainly the ECU is providing errors and I'm pretty sure that is a Ford one. I have had a look at the 7M5919506 relay/module connections. This part seems to be used in Fords and Volkswagens and other cars. I found some brief info on it that is not quite correct, but it certainly is there to control/drive both Fans. I have powered both Fans and they both run fine.

The 7M5919506 has 2 pins for each of the Fans (separate relays or MOSFET PWM control ?). One Fan is connected to +12V and the relay switches the other wire to ground and the other Fan is connected to ground and the relay switches the other wire to +12V. With this I guess the "relay" has 12V and Ground for its probably electronics part.

On the 3 other pins, one document I saw stated one is set to 12V for engine run-one Fan operation and the other two are from the ECU possibly enabling each fan separately but could also be doing other things. Without the relay plugged in so I can get at the connections the three "control" pins say stubbornly at 0V even with the engine running and AC turned on. I was expected one of these "ECU" (or rely driven ?) control lines to go high with the AC on.

[TomsFocus]

That does sound complex for the time.

I was expecting just one fan with two speeds.  With two fans at that age it could be one used for engine cooling and the other used for AC.  Or they may both be used together but at either full or half speed depending on the engine & AC requirements at the time.

I'll tag @unofix as he's better with this sort of thing than I am!

[Terry Barnaby]

Yes, I think one Fan may be primarily used for AC and the other for engine cooling. However they could be used with one for 1/2 power and two for full power. There are no resistors for the Fans. Either the Fan control "relay" switches one or both on for a degree of control or has some form of PWM variable speed control (I think the 7M5919506 relay/module is pretty basic, so probably just relays). The AC "radiator" goes in front of both fans. The engine radiator is just behind it (not sure it is full or half width).

Thanks.

[unofix]

As it happens I owned a 1998 2.3 Galaxy Ghia and then a 2001 Galaxy Ghia both petrol, both manual.

The 2.3 petrol engine was 100% Ford as was most of the control equipment that went with the engine. The A/C systems were largely VW especially those that had the full climate control which was taken straight from VW.

Fortunately I never had need to investigate the cooling fans, other than I remember that one fan would run all of the time if the Climate control was on, which on those models was all of the time unless you made a special effort to turn them off.

It was also very common for the cooling fan to run for several minutes after switching off the ignition.

I'll have a look and see what if any info I have regarding the electrics.

I've attached the schematics for the 2.3 Petrol Galaxy as sold in Europe (not in English) but electrically it will be the same.

2001-galaxy-elektricka-schemata.pdf

[Terry Barnaby]

Many thanks for the circuit info. There are about 6 or so different circuits for the Fan control ! Amazing for something so simple.

Unfortunately none of them "appear" to match what I have, the one on Page 135 appears the closest (One fan switched to +12V and the other switched to Gnd). But the relay pin numbering is all wrong, there appears to be an extra motor (Fan ?) and there appears to be an extra pin in use. Maybe the control relays before match ...

[Dan62]

The attached should be what you're looking for.
See Personal Message I've sent if you need AC info.

Galaxy Cooling.pdf

[Terry Barnaby]

Many thanks, that looks close to what I have although the K45 fan connection pins numbers appear to be transposed, but that depends on the actual K45 relays pin numbering. The 7M5919506 has pin numbers on it that definitely do not match the schematic, but I have seen another document for a Ford that states numbers are for the socket not the relay. That appears to then match the schematic.

From that it looks like pins 7, 9 and 6 are the control lines. Pin 6 looks like it should go high to +12V when Fan run on is activated some how via S97.

I assume pin 7 and 9 should enable the individual fans and pin 6 turns on one or both of them. There is 120 Ohms between 7 and 9, so a relay coil I guess.

Pin 6 is quite high impedance to 7 and 9 (> 5 MOhms), so possibly electronics there

Not sure on N349, appears to pull 9 to 0V unless rad > 100C  or opens when rad > 100C ?

With aircon on and no relay pins 7, 9 and 6 are 0V ...

I will do some more meter probing, but maybe the issues is with the PCM or the lines from this.

Not sure if I need AC info, I guess it depends on how that ends up switching the fans on.

 

[Dan62]

C37 (K45) pin numbering is bizarre. Image should be socket view.

[Terry Barnaby]

On mine it is actually different to that (I think!)

--7   -- 2  --8

---3          |5

--6  --1  --9

This appears to match the schematic, well at least pins 3, 1 one relays contacts and 1,5 second relays contacts appear to be correct and have +12, GND and the Fan motors connected as per the schematic.

Now I've got to work out how that "relay" actually works! and if N349 should be shorted when below 100C or when above 100C 9which would make more sense).

There is 60 Ohms between 7 and 8 and 60 Ohms between 9 and 8 (so 120 between 7 and 9). Pin 8 is not connected ... I would have thought pin 8 should be +12V then the ECU would pull down 7 and 9 for each fan, but pin 8 is not connected ...

[Terry Barnaby]

I am slowly getting there, but still not sure where the problem actually lies. There is so much misinformation and errors in documents and other things!

I can see the ECU pulls pin 7 and pin 9 low to enable the two fans (other documents say they are pulled high). The two relays coils other sides are connected to pin 8, but this is not actually connected! However I think pin 6 is possibly connected to pin 8 via a diode in K45.

I have connected pin 6 of the K45 engine cooling fan relay to +12V and everything seems to work. No engine fault codes, AC works (with one Fan coming on) and one Fan comes on when engine around 98C or so.

K45 pin 6 is connected to +12V through K151 Engine cooling fan run on relay which appears to be powered through K108 Power relay. There is also M151 cooling fan run-on coolant pump but when I put +12V on pin 6 with engine off, no current is drawn. So I appear not to have this pump or it is not working.

1. I would have thought the K151 Engine cooling fan run on relay would only switch on during fan run on, but maybe it is miss-named and it switches on the fan power to the K45 relay so enabling the fans.

2. The K108 Power relay appears to be always energised from the schematic, at least when the battery is connected the correct way round, this seems strange (battery run down) ?

Anyway I am going with the idea than K45's pin 6 should be at 12V and possibly K151 or K108 is faulty or their switch on signal is faulty. However I have no idea how to find these relays. I assume they are under the dashboard with the fuses. There are two layers of relays behind this, but no information as to which is K151 or K108. Any idea how I work out which/where these relays are ?

[Terry Barnaby]

Ah found it. In the previous schematic unofix provided it had near the end listings of the relay positions 🙂

Having done that I finally traced it to a blown 5 Amp fuse, F18, which is marked with an icon that is now obviously one indicating engine cooling (why can we have text for things rather than just icons written in the user manual) ! I was pretty sure I checked all of the fuses first ....

Obviously not sure why it has blown, but maybe it was on the edge in a 22 year old car. I will keep a spare. Mind you are am now using a second hand K45 rather that the original one in the car.

Anyway it looks like the K151 Engine cooling fan run on relay is always engaged to power the fans when the engine is running and I guess stays engaged for a time after engine switch off. And the themo switch, N349, must switch on at 100C rather tan switch off which the schematic suggests. I wonder if my car has an electric coolant pump as well as the mechanical one and it has gone ?

Anyway thanks all, the schematics helped a lot and the car can keep going, even with AC, for a bit longer 🙂