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Ok, I think the big 'relay' is the headlight washer timer.

I wonder if that relay in same picture 2 mounted on air cleaner mount is for your cooling fan?
That one is the A/T cooler fan relay from the wire colours.

So I think it must be one of the three despite no brown wire.

There is one with a 10A fuse which I think is headlight and two with 30A fuses one of which is the horn and since all the fan wiring is on this side, I'm guessing it's the other 30A fused relay.
 
Discussion starter · #25 · (Edited)
Thanks Craig. Here's what I have:

1. Inboard relay in RH cluster is LH LOW BEAM. Serviceable.

2. Relay on airbox is AUTO TXN FAN. Fan works with pins jumped and assume relay is serviceable.

3. Inboard relay in LH cluster is HORN. Serviceable, much to the joy of my 3yo daughter who was employed as the horn pusher while I was under the bonnet :eek:
4. Centre relay in LH cluster is RADIATOR FAN (Coolant Temp). Serviceable and fan cycles religiously with a warm engine.
5. Outboard relay in LH cluster is RH LOW BEAM. Serviceable

6. We assume the two relays on the radiator are MOTRONIC ?.

7. This leaves the large relay outboard in the RH cluster as a mystery :confused:.
This relay plugs into a blue base.
It has Bosch PN: 1 397 328 006 marked on it.
The relay has 5 pins, with associated wiring as follows:
P= Grey/Blk (thick wire)
S=2x White/Blk wires
31= 2 Black wires
56= 2x Yellow/Blk wires
30=Red/Blk (thick).

:confused:Guesses anyone :confused:
 
Discussion starter · #26 ·
So given the previous details, I know the rad fan is good, as is it's associated relay.

Next I need to work out how the fan is actuated with high pressure in the AC. I'm unsure whether the pressure switch directly activates the aforementioned RADIATOR FAN RELAY, or if there is an additional relay somewhere.

The rec/dryer has a switch in the end with 2x Blue, and 2x Blk/Green wires. It also has 3 pressures stamped on it, which I assume means that the switch activates differently at each pressure. The pressures are:
H/P 27 KGcm2
M/P 15 KGcm2
L/P 2 KGcm2.

More assumptions on my part (please correct any misinformation) are that the low pressure would switch the system off, not allowing power to the pump pulley magnetic clutch. Medium pressure would activate the radiator/condensor fan. High pressure once again deactivates the system. ??????????????????

First pic shows the Rec/Dryer.
Second pic shows an adjustable switch/gadget on the rec/dryer (cover removed). What's this for ???.
 

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Discussion starter · #28 ·
I did discover another relay near the hot 12V connector and fusible link on the rear of the false firewall. Anyone know what this one is for ?
 

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Discussion starter · #29 ·
Same guess as before, headlight washer timer.
Craig,
:confused::confused::confused:
I didn't realise the headlight washers were timed. Don't they simply activate along with the screen washers ?
:confused::confused::confused:

Please elaborate ....................... :eek:)
 
So given the previous details, I know the rad fan is good, as is it's associated relay.

Next I need to work out how the fan is actuated with high pressure in the AC. I'm unsure whether the pressure switch directly activates the aforementioned RADIATOR FAN RELAY, or if there is an additional relay somewhere.

The rec/dryer has a switch in the end with 2x Blue, and 2x Blk/Green wires. It also has 3 pressures stamped on it, which I assume means that the switch activates differently at each pressure. The pressures are:
H/P 27 KGcm2
M/P 15 KGcm2
L/P 2 KGcm2.

More assumptions on my part (please correct any misinformation) are that the low pressure would switch the system off, not allowing power to the pump pulley magnetic clutch. Medium pressure would activate the radiator/condensor fan. High pressure once again deactivates the system. ??????????????????

First pic shows the Rec/Dryer.
Second pic shows an adjustable switch/gadget on the rec/dryer (cover removed). What's this for ???.
Your newly found fan relay between horn and headlight relay on euro version must mean you have a single speed cooling fan or do you have dual cooling fans like GTV6 w/AC?

As for your uncovered switch in picture that is frost switch which is wired into side of trinary switch Q20 that engages/disengages compressor clutch if pressure low, extremely high or evaporator freezing up.

Other side of trinary switch is medium high pressure side that grounds cooling fan relay when freon pressure hits 215psi. Ground that brown wire to black wire in chassis wiring going to switch connector and see if relay clicks and fan works. If not ground brown wire to see if black ground bad.

If fan works doing these tests and not with a/c pressure trinary switch with freon medium high pressure then side of switch bad or plunger not opening valve core in receiver dryer (later not likely if compressor engaging).

If you have a second fan and second relay find it. Some 164s had two fans accorfing to part CD.
 
I did discover another relay near the hot 12V connector and fusible link on the rear of the false firewall. Anyone know what this one is for ?
In these pictures rear 40A fuse bar is for blower motor and relay next to it is for blower motor.

If you have matching front side of false firewall fusible link 40A fuse bar it is for cooling fan motor.
 
Discussion starter · #32 · (Edited)
In these pictures rear 40A fuse bar is for blower motor and relay next to it is for blower motor.

If you have matching front side of false firewall fusible link 40A fuse bar it is for cooling fan motor.
Nope, just the one fusible link :).

I placed a jumper wire across the black and brown wires at the 2-pin plug, and the radiator fan activates perfectly.

So, it all points to a failed trinary switch on the rec/dryer ?

I should be able to test this switch, shouldn't I ? If I disconnect the 2-pin plug, then connect a meter across the black and brown connections of the trinary switch, I should see continuity across these wires once the pressure rises to 215PSI. I assume this happens soon after the AC is switched on ?

Given my mechanic was seeing high pressures, I can assume I'm getting pressures adequate to close a serviceable Tri switch.

Feasible ??????

---------------------------------------
Something else I found is that I have a cut wire adjacent to the frost switch.
The switch currently has a thin grey/blk wire connected, and wrapped in the same loom there is a grey/green wire that has been cut. I can't find the other end of this grey/green wire.

The other wire on the frost switch is a thick green wire, and it disappears into a different loom to reappear under the RH corner of the windscreen and then it goes through the firewall. It's the only wire going through this firewall hole.

The thickness of the green wire ponts to it being non-original, but the way it's wrapped in the loom makes it look factory ??? Maybe the green wire was added to bypass the grey/green wire at some time in the past.

If anyone feels so inclined, I'd appreciate details on wire colours as attached to your frost switch.
----------------------------
 
Nope, just the one fusible link :).

I placed a jumper wire across the black and brown wires at the 2-pin plug, and the radiator fan activates perfectly.

So, it all points to a failed trinary switch on the rec/dryer ?

I should be able to test this switch, shouldn't I ? If I disconnect the 2-pin plug, then connect a meter across the black and brown connections of the trinary switch, I should see continuity across these wires once the pressure rises to 215PSI. I assume this happens soon after the AC is switched on ?

Given my mechanic was seeing high pressures, I can assume I'm getting pressures adequate to close a serviceable Tri switch.

Feasible ??????

---------------------------------------
Something else I found is that I have a cut wire adjacent to the frost switch.
The switch currently has a thin grey/blk wire connected, and wrapped in the same loom there is a grey/green wire that has been cut. I can't find the other end of this grey/green wire.

The other wire on the frost switch is a thick green wire, and it disappears into a different loom to reappear under the RH corner of the windscreen and then it goes through the firewall. It's the only wire going through this firewall hole.

The thickness of the green wire ponts to it being non-original, but the way it's wrapped in the loom makes it look factory ??? Maybe the green wire was added to bypass the grey/green wire at some time in the past.

If anyone feels so inclined, I'd appreciate details on wire colours as attached to your frost switch.
----------------------------
Yes feasible!

OK here is how mine wired, Red connector has 2 green wires at Q20 trinary switch one has gray-black wire going to frost switch as yours is and other green wire goes to another green wire in red connector back to a/c ECU Q21a dash panel pin 28.

Other side of frost switch wire gray-green (now green in your car) goes to pin 85 of a/c compressor clutch relay Q22 behind instrument cluster. Can you hear a relay click behind speedo when you hit auto button on dash panel when compressor clutch engages with key on engine off?

I doubt your new green wire at frost switch is same wire as one going to ECU on mine. Maybe somebody made a repair but who knows why they cut green-gray wire and replaced it with larger green one.

As for trinary switch testing you will need to have a/c gage set installed to see if when high side reaches BETWEEN 210 to 239 psi (14.5 TO 16.5 BAR) to see if the switch makes the blue wires in the white connector close making a ground for fan relay.

If switch is bad and your summer is upon you, you can jumper wires so fan on when you turn key on so a/c won't over pressurize until you can get a new switch.

There should be a valve core in receiver dryer so you can remove switch with freon in system (should be I say proof is in removing switch). Be sure you get correct switch replacement with a plunger to open valve core as we had one guy on here with wrong switch so compressor wouldn't engage since it couldn't read even low pressure.

The things people do to cars to baffle the next owner just amaze me all the time.

Never can you assume anything just like why do you have green wire in place of green-black original wire?
 
Discussion starter · #35 ·
Craig,

Rings a very vague bell,. but that was a few Alfas ago and I don't recall details.

It's easy enough to check if the large relay is for the headlight washers, I'm just confused why it would have a timing function.

Steve,
thanks for the great advice, I'll check it all out. I'm flying interstate until Thursday so the troubleshooting will be on hold.

I suspect the green/grey wire may have been damaged at some time, hence the addition of the green wire. There are lots of telltale signs that this car has had a substantial amount of extra electrical devices fitted at some time, and wiring may have been damaged on instal/removal.

I removed a ton of sound system wiring, integrated phone system, and there are brackets I assume would have been for an aftermarket alarm system. I've also found a few of those 'quick' wire connections that lamp/pierce existing wiring to tap power off to additional devices, though the additional wiring is long gone.
 
Discussion starter · #37 ·
Yeah,

Strange that there isn't a separate switch for headlamp squirters. BTW, you really shouldn't be awake at 1.30 am ;)

STEVE: I don't have any relay noises emanating from behind the dash when I select the AUTO/ECON switches with the ignition key off ?? Surely these relay wouldn't get power in this situation as they would get hot and sap power :confused:
 
Yeah,

Strange that there isn't a separate switch for headlamp squirters. BTW, you really shouldn't be awake at 1.30 am ;)

STEVE: I don't have any relay noises emanating from behind the dash when I select the AUTO/ECON switches with the ignition key off ?? Surely these relay wouldn't get power in this situation as they would get hot and sap power :confused:
No, only when you select auto mode button on A/C panel to engage compressor clutch will Q22.
relay be energized to engage clutch, do you hear clutch engae when you push auto mode button? If not, check to see if clutch already engaged when you start engine as somebody may have modified wiring. You don't want compressor clutch engaged when not selected especially if trinary switch not turning cooling fan on properly.

On USA models you have 4 relays behind speedo - I50 high beams relay, I70 radio relay, I62 A/T selected gear signal, and Q22 compressor clutch relay.
 
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