AFN wiring

[NickBab]

Hi all,

I'm making progress with my Passat AFN engine with Landy pump swap but have hit a bit of a stumbling block re the wiring. I've been googling for a while but I'm struggling to find the equivalent JX sensors on the AFN block.

In particular the AFN equivalent for:

Brown/red JX wire (Thermoswitch for coolant circulation run on)

Blue/Green JX wire (Coolant Shortage indicator sensor)

Blue/White JX wire (Oil Pressure Switch 0.3 bar)

I think I'm OK with the other wires so should be able to get the engine running. It'll be nice to get as many of the manual warning sensors working though.

Does anyone know the location of the above or if they exist on an AFN Passat engine?

Help would be very much appreciated.

Thanks
Nick

[lloydy]

Hi all,



In particular the AFN equivalent for:

Brown/red JX wire (Thermoswitch for coolant circulation run on) not fitted on the afn donor

Blue/Green JX wire (Coolant Shortage indicator sensor) no idea if its on the afn loom

Blue/White JX wire (Oil Pressure Switch 0.3 bar) not fitted on the afn donor, it just has the one on the oil filter housing

I think I'm OK with the other wires so should be able to get the engine running. It'll be nice to get as many of the manual warning sensors working though.

Does anyone know the location of the above or if they exist on an AFN Passat engine?

Help would be very much appreciated.

Thanks
Nick

isn't the whole point of going mtdi to just use the jx loom? To that end just fit the jx senders on the afn engine and connect to the jx loom

[NickBab]

Thanks Lloyd,

The wire colours I mentioned are the JX loom, the question was is there equivalent sensors on the AFN engine to connect these to? Looking at your reply I guess not. I couldn't find these through googling either.

Not sure I understand re connecting the JX senders to the AFN engine?

I already have the glow plugs, fuel pump and oil pressure sensor on the filter housing connected via the JX loom, just trying to figure if/where to connect the final wires from the JX loom.

[lloydy]

ok, get you. The 0.3 oil pressure switch goes on the back of the head, the afn won't have one there. So just remove the switch from the jx, remove the blank from the back of the head on the afn and fit the switch.

Coolant shortage, do you mean the one on the coolant reservoir? If so, just connect to that

The coolant run on... People don't normally connect this back up on a tdi as they don't run hot enough. My pump is removed and the hoses joined together.

[NickBab]

Thanks again Lloyd, very useful info.

I looked on the back of the head for the 0.3 pressure sensor but couldn't see one there. I didn't realise there was a blank. I'll look at the workshop today.

I'm pretty sure the coolant shortage and run on wires connected to the back of the block near the coolant hose on the JX. Good to know I can dump the run.

It looks like the AFN has 3 sensors in the same location, but I'm struggling to find anything online to say what these are. The pic below is taken from underneath the AFN and at the rear of the block.

Any idea what each of these are?

[lloydy]

They are coolant glowplugs, and are operated by the ecu. So either leave in and ignore or fit a different flange without the plugs (like the jx one)

[NickBab]

Got it, thanks. I'll just leave them in, unused.

So I'm just down to 1 stray JX loom wire now. I thought it was blue/green, but looking at the JX wiring diagram this suggests this goes to the coolant shortage sensor. Like you I thought this sensor was on the coolant bottle though so maybe I got the colours wrong. I'm pretty sure this stray wire went to the back of the block, near the temp run on switch on the JX. Is there a 3rd sensor on the back of the JX? 0.3 pressure, temp run on + one more?

My memory is not what it used to be, I'll check at the workshop today.

[syncroandy]

From my notes:

Ref Description Wire colour Sender part number Colour

F95 Thermoswitch for coolant circulation run-on Brown/Red & Brown 251 919 369 F Brown
G27 Sensor for engine temperature (glow plugs) Blue/White & Brown 251 919 501 A, 251 919 501 D Black
G2 Coolant temperature gauge sender Yellow/Red & Brown 251 919 501 A, 251 919 501 D Black

Oil switches are:

F1 0.9bar (flange) Yellow
F22 0.3bar (head) Blue/Black

HTH

PS. The above part numbers are for the 20mm 2-pin push-in senders used on 'late' JX's, if you have an early JX van it will have the single-pin screw-in senders which are fitted to aluminium flanges which you will to swap onto the AFN.

[NickBab]

From my notes:

Ref Description Wire colour Sender part number Colour

F95 Thermoswitch for coolant circulation run-on Brown/Red & Brown 251 919 369 F Brown
G27 Sensor for engine temperature (glow plugs) Blue/White & Brown 251 919 501 A, 251 919 501 D Black
G2 Coolant temperature gauge sender Yellow/Red & Brown 251 919 501 A, 251 919 501 D Black

Oil switches are:

F1 0.9bar (flange) Yellow
F22 0.3bar (head) Blue/Black

HTH

PS. The above part numbers are for the 20mm 2-pin push-in senders used on 'late' JX's, if you have an early JX van it will have the single-pin screw-in senders which are fitted to aluminium flanges which you will to swap onto the AFN.

Thanks Andy, that helps explain what's going on.

I must have noted some of the colours wrong as some things didn't make sense when going through the wiring diagram last night. I'll double check today.

I have the single pin senders so swapping the flanges makes more sense rather than trying to find the equivalent AFN senders.

Are F95, G27, and G2 all on the same flange at the rear of the JX block? Hopefully the part numbers are on the senders still so I can figure what is what.

Not working today so off the workshop soon, hopefully it'll all make sense once there.

[NickBab]

OK, sussed

G27, G2 are on the rear flange. Both the same sensor.

F95 is on the side flange although my sensor is a different part number 251919521

Wires match Andy's colours so all good.

Thanks for your help
Nick