[ASTOBBS]

Have started to make some progress on this today. I have taken the complete aircon system and whole front wiring loom from an x20xev engined vectra B LS, with the intention of fitting it onto my x18xe engined 1.8GLS

First issue in point, is that vauxhall's beautiful 'plug and play' wiring does not extend to aircon. My GLS has none of the required wiring for aircon, so first task has been to make the decision between

1.Swap 2.0 front looms over in their entirity
2.Make my own really simple loom that incorporates non of the original features
3.Add in the required bits for full A/c functions as vx intended.

Its nuts the amount of loom variations, the 2.0 loom has all the wires I need except one - the plug for wiper stalk buttons to flick through the MID with. It had everything else that you would never expect of an LS. eg. cruise control, heated front seats, although it had non of the alarm loom, which wouldn't have mattered to me as I've got an aftermarket alarm.

So that left 2 options, and I'm a glutten for punishment so I'll be going for option 3.

Have made a start tonight on tracing through all the A/c related wires on the 2.0 loom, so that I can eventually cut them out and thread into mine. The white plug that lives on the battery tray handles the controling of the A/c.
So I've worked outwards from the dash switch following wires and noting where they go, and then worked back in from the white plug for the wires that hadn't already been covered.

My only other hitch is that when I took the aircon off, there was no refridgerant in the system, which was a mixed blessing, on the good side I didn't have to worry about it myself, and on the bad side it leaks!
Leak proved to be from the rubber section that runs next the power steering pump pully, the aux belt has rubbed through it, not quite sure how to repair that yet, will probably go to the local hydraulic place and see what they can do, or just find another pipe set on a second car.

Will keep you all posted as I progress.

[Leeky]

You like being in at the deep end! lol. You sound as bad as me.

You've made the right option with running the loom alongside the existing loom. If you wire it as it should be you can then run diagnostics through the diag port as well - Always a bonus!

Keep us updated, and pictures are always good.

[ASTOBBS]

As a little adendam to this, I have now bought all the kit req'd for the electric rear windows. Bought the vectra main switches, then the vectra door switches, then saw a full kit on ebay from an omega with the regs, looms, all switches, tweeters etc. So have bought that aswell for the regs, I'm told the omega regs drop the glass the whole way down, which can only be a plus really, and the C/L plug is different that the vec, so I will be splicing two looms into one most probably.


Have not done anymore on A/C yet, will have a probe around tomorrow with multimeter. Want to get it crystal in my head, so I can install all the wires in one hit, while the dash is out to get to the heater housing, don't want to be taking the dash out twice haha.

Will get pics of anything note worthy, but wires are pretty dull really.

[Leeky]

Do you have the rear window wiring in place already then? Or you retrofitting the rear wiring loom into the main loom as well.

[ASTOBBS]

	Quote:
	Originally Posted by Leeky Do you have the rear window wiring in place already then? Or you retrofitting the rear wiring loom into the main loom as well.

thanks to the guide on here (how I stumbled onto this forum) I have checked, and the wiring in the main loom is there, well it is on the N/S, hopefully it is on the O/S too!

Wierd the way VX made so many looms, but I suppose when they are making however many thousand of a particular low spec loom, the amount of wire saved soon mounts up.

[ASTOBBS]

Have spent the whole of today blundering my way through wiring loom and now have a good undertanding of the actions and reactions that take place within the car when the Air con is being used or not being used. I'm still working on the actual operation of compressor and fans etc.

This bit now is boring but I will post incase someone picks it up in a search and can save themself alot of thinking:

3 extra relays are present in the fuse box of a car with aircon,
these being 1 brown and 2 Greens

The greens are standard switching relays, 4 terminals
T85 & T86 making up the low current side
T87 & T30 being the switched pair on high current side

The brown is a 5 pin NO/NC combination relay
T85 & T86 making up the low current side
T87 & T87a are NC
T87 & T30 are NO

The brown is the first relay to consider,

T85 - Brown wire, Direct to GND
T86 - Black wire - IGN Switched +12v
T87 - Red with black tracer
T87a - Red with white tracer
T30 - Red +12v Perm. Via 30A fuse in fuse box

Upon switching on the igniton to setting 2 (ie running conditions)

T87 Supplies +12v to;
Both green relays on their T30's
The Red/black wire in the white plug on battery tray which controls Fans etc.
The Red/black wire at the rear of the heater fan selector

UPPER GREEN RELAY - Forces Blower fan into Speed 1 when Aircon is called for

T85 - Brown GND
T86 - Black with white tracer - signal from dash AC switch
T87 - Blue
T30 - Red/black from brown relay T87

If the Aircon is not being used Upper green relay is redundant, upon receiving +12v on T86, the blower fan is forced to run at speed 1 to ensure airflow across the evaporator.


LOWER GREEN RELAY - Switching relay for blower speed 4
T85 - Brown GND
T86 - Black with yellow tracer
T87 - Green
T30 - Red/black from brown relay T87

When the blower fan is running on speeds 1,2,or 3 regardless of AC status this relay is redundant.

Upon receiving +12v on T86. T87 is connected to T30 bringing the blower fan upto speed 4.


DASH SWITCH - viewed as if looking into the socket with switch removed


1

( )2

3( )4

1. Grey with yellow tracer - backlight supply, +12v when sidelights/headlights are turned on

2.Black with green tracer - IGN switched +12v feed

3.Brown, direct to GND

4.Black with white tracer. When AC is called for, this completes the circuit with 2 to illuminate the AC indicator lamp, and also Provides signal to Upper Green relay as discussed above, AND also carries 12v forward to white fan plug on battery tray as discussed above.


HEATER CONTROLS - viewed by looking at the contacting side of MALE plug, orientated as it is when plugged into heater controls. (contacts themselves female)

1 2 3
4 5 6
7 8 9

1.Grey with yellow tracer, backlighting of contols when lights are on

2.Brown GND

3.Brown with green tracer, to Air recirculation servo. Connects with ground(and supplies GND to air recirc servo) on all distribution settings except windscreen demist - to prevent moist air being recirculated when on demist setting.

4.Red/black Main +12v feed into blower fan speed selector, from brown relay as discussed above.

5.Brown with white tracer, connected to ground when set to cold air, control of vacuum operated matrix bypass valve.

6.Black with yellow tracer, blower fan speed 4 - signal to lower green relay as discussed above

7.Grey, blower fan speed 2. Supplies +12v to blower motor for fan speed 2

8.Blue, blower fan speed 1. Supplies +12v to blower motor for fan speed 1. Can also receive +12v from upper green relay as discussed above

9.Yellow, blower fan speed 3. Supplies +12v to blower motor fan for fan speed 3.


BLOWER FAN MOTOR PLUG - viewed from contacting side of male plug (contacts themselves female)

1 2
3 4 5

1.Blue speed 1
2.Green speed 4
3.Grey speed 2
4.Yellow speed 3
5. Brown GND

All the above as found in wiring loom of X20XEV LS hatch model.

Currently unsure how wiring for blower and controls are laid out in a non AC model - will update when I have my dash out and can see clearly.

[Leeky]

Nice post mate!

It will be interesting to find out the differences between AC and non-AC systems.

Though I dare say a spreadsheet would show it better in this case.

Good work though, and I look forward to seeing pictures of you getting it done.

[Leeky]

Nice post mate!

It will be interesting to find out the differences between AC and non-AC systems.

Though I dare say a spreadsheet would show it better in this case.

Good work though, and I look forward to seeing pictures of you getting it done.

[ASTOBBS]

So so lets pick this up and move into the relays under the bonnet that relate to all fan operations and compressor clutch.

This is quite a lot of information to absorb, I will try to write it as simply as possible so forgive me if its a bit slow at times; and when you're still confused having read it through 5 times, think how long it took to work it all out!

So in the last post, I got as far as detailing the operations of the 3 relays in the fusebox, the heater switches, the A/C dash switch, the re-circ servo, and the matrix bypass valve.
I did not get as far as completely detailing the white plug which I mentioned earlier, so first we will look at the 9 wires which lead to this plug.

At times, I will simply refer to wires as IGN Switched Live - Ignoring the fuses they pass through on the way for the moment.

So starting with the white plug that is on the end of the main loom we have 9 wires.

1.R/w from T87a Brown relay in fuse box
2.R/b from T30 upper green relay in fuse box
3.B IGN SWITCHED
4.B IGN SWITCHED
5.Bn/Pp to ECU
6.R Perm +12v from F22
7.B/Bu To ECU
8.B/w To ECU
9.B/w From Dash A/C switch

Now dealing with the other end of the white plug, ie. the end connected to all the fans and switches and relays etc.

1.NOT USED
2.B/r
3.B
4.B
5.Bn/Pp
6.NOT USED
7.B/Bu
8.B/w
9.B/y

Right, now I need to outline just what is connected to this second white plug, be it indirectly or directly.

2 Fans, one on water radiator, one on the A/C condenser (aircon rad)
7 Relays, 2 in a small box 5 in a long box
2 fuses 30A, in the small relay box
2 Radiator temp sensors, one a round 3 pin plug, one a flat 3 pin plug
2 AC pressure switches, one a square 4 pin plug, one a flat 4 pin plug
1 AC compressor plug

In the short relay box, is a standard green switching relay 4 pins, and a special brown (not the same as other browns) which can be switched by two independant wires. It has pins 85, 85b, 86, 87, 30, 85 and 85b will both energize the relay. relays in the short box wil be referred to as G or B

In the long relay box, there are 2 greens which are standard switching relays, 2 browns, which are the same as the brown in fusebox and a grey which is a twin jobby, able to switch two circuits as opposed to just one as per a green relay.
green 1 is the green relay closest to the end of box in which the wires enter, green 2 is the further away of the two, ditto for the browns. The grey will be reffered to as GREY.

I'm not going to attempt to put a wiring diagram up here, it'll be hard enough to draw on paper, let alone try and make it pc friendly.
I will instead describe a series of events, from both an action and reaction angle and try to give the reader an understanding of current flow.

Lets say the car is moving and we have good airflow across the rads, the engine is at a good operating temp. and the aircon is not being called for by the driver. No fans run, infact in terms of actual current flow within the whole sub-loom nothing is happening.

We hit some traffic but maintain forward speed, however rad temp climbs to 100 c, the round rad plug switches from open circuit to closed circuit between pins 1 and 3. Pin 1 is permanantly grounded, so pin 3 now receives a gnd signal. This is taken via Bn/Y wire to G2 T85.

G2 Terminals

T85 Bn/y from round rad temp
T86 +12v perm.
T87 R/w
T30 +12v perm.

Because T86 is +12v, and upon receiving the signal from the rad switch, T85 is GND, the relay switches, and supplies 12v onto the R/w wire at T87, this red and white wire goes then onto B1 T30

At B1 we have the following terminals

T85 Bn/w
T86 IGN Switched 12v
T87 R/w
T87a R/y
T30 R/w from G2

B1 is at rest (ie. un-energized) so T87a and T30 are closed circuit, therefore power flows to T87a and out to the AC fan via a R/y wire, having reached the AC fan and gone through the motor windings, this power then returns on the Brown and white wire from the AC fan upto T30 B2,

B2
T85 Bn/w (light)
T86 IGN Switched 12v
T87 GND
T87a R/w
T30 Bn/w (heavy)

At this point B2 is also at rest so T30 and T87a are closed circuit, therefore the circuit continues on from the AC fan to the R/w wire at T87a, this wire changes colour shortly after leaving the relay to R/y and makes its way to the rad fan.

As a result, both fans are now connected in series, and a perm. GND connected to one side of the rad fan completes the circuit.
Both fans effectively run at 6v ie. Speed 1

Ok so now the rad temp has reached 105c, the fans are already running at stage 1, but the round rad plug now makes a second connection, it switches so that pins 1 (gnd) and 2 (Bn/w) are now closed circuit. Pins 1 and 3 remain closed circuit.

So we now have a GND signal on the Bn/w wire, this wire is common to 3 relays G1 B1 B2

So now G1 B1 and B2 are energized,

as G2 is still supplying 12v to B1 at T30

But now B1 has switched, T87a and T30 are no longer connected, instead T30 and T87 are now closed circuit, so the 12v supply is now routed into T87 which supplies the AC fan with its own 12v feed. And removes the feed via R/y which was the series connection.

B2 Also switches, which means that T87a and T30 are no longer connected, instead T87 and T30 are now closed circuit, knowing that T87 is perm. GND, GND is now available at T30, which allows the AC Fan to have its own GND on the heavy Bn/w which previously provided part of the connection with the rad fan when in series operation.

So the AC fan now has its own 12v feed, and GND, however on each fan is a resistor, and in this configuration the resistor is being used to slow the speed of the fan, thus giving speed 2 running.

ALSO G1 has now also been energized,

G1
T85 Bn/w
T86 IGN switched 12v
T87 R/w (heavy)
T30 perm. 12v

As G1 has now been energized, power from T30 can flow to T87 and in turn down to the rad fan via R/w wire, and utilising the rad fan's own resistor speed 2 is acheived, with the rad fan GND completing the circuit.


Now the rad temp is getting pretty damn warm, at 110c were stuck in traffic on the world hottest day, its mega humid and the leather work is visibly shrinking as you sweat it out without the Aircon on.

We are already running at speed 2, now the flat rad temp plug plays a part and connects pin 1 (perm GND) to pin 2 (Bn/w - NOT TIED TO ANY PREVIOUSLY MENTIONED BN/W) this second Bn/w wire carries a GND signal upto the two relays in the short box, G and B

G
T85 Bn/w from flat rad temp switc
T86 IGN switched 12v
T87 R/y
T30 Perm 12v

Having now been energized 12v flows onto T87 via T30 and down a heavy red and yellow to the RAD fan. This is eventually the same wire as was used in speed 1, it actually joins on in the long relay box.

So now the rad fan has +12v on the R/Y line which bypasses the fans resistor and gives full power to the rad fan ie. Speed 3 the rad fans dedicated GND wire completing the circuit.

Brown relay

T85 Bn/Y
T85b Bn/w wire as above from flat rad temp.
T86 IGN Switched =12v
T87 R/Y heavy
T30 perm. 12v

T85 is used by the Bn/w wire to energize the B relay, thus providing power onto T87 which eventually goes to the AC fan on the same red/yellow wire as was used in speed 1 operation, (the wire actually joins on in the long relay box) and so the AC fan now has 12v without the resistance in circuit and is still recieving GND in the same manner as speed 2. so now both fans are at full tilt.

[ASTOBBS]

Right so we've just cooked the rad for a while, now we have cleared the traffic jam, its still dead humid, and we've got good airflow across the engine and rads. The rad temp is down below 100c so no fans are running.

Time for the aircon : )

The dash button is pressed and all of the things mentioned earlier within the cab happen, AND 12v is sent forward to to the sub loom via the white plug on pin 9.

This Supply is carried to what haynes refer to as the triple switch, what I've seen reffered to as Trinary switch. This is the flat 4 pin plug mentioned in the previous post which clips onto a pressure switch on the AC line.

This 12v is sent to pin 2,

Pin 1 - B/w to ECU via white plug p8
Pin 2 - B/y From Dash switch via white plug p9
Pin 3 - B
Pin 4 - B/Bu to ECU via white plug p7

I'm moving a little into guess work now as I can hardly find any info on these triple switches, and have not got the facilities to simulate high pressure as it would be on the AC line.

I can however simulate 2.5 Bar which I believe is the minimum pressure the ECU want's to see on the AC line before it will consider switching the AC ON. With 2.5Bar on the line, pins 1 and 2 go closed circuit.

SO I'M ASSUMING THAT on finding 2.5Bar on the AC line (the AC will not activate at extremly low pressures to protect the compressor unit) the ECU then checks that the outside temperature is more than 3 c.

AGAIN AN ASSUMPTION, it could be that the gas used will not produce 2.5 below 3 c and the ECU does not actually have the facility to ping the outside air temp sensor. Infact I've a feeling the outside air temp sensor is driven purely by the TID/MID, please confirm/deny if you know.

So anyway, the ECU goes ahead and allows the AC to run, it does this by emitting GND on pin 5 of the white plug, Brown and Purple wire.

This Bn/pp wire goes to the GREY relay in the long box

GREY
T85 Bn/Pp GND signal from ECU when cond. OK for Aircon
T86 IGN. switched 12v
T87 Bn/Y
T30 GND
TA IGN Switched 12v
TB B/w Compressor Clutch

So the Grey relay is energized, T87 and T30 are now closed circuit so GND is emitted onto the Bn/Y wire, which tees into the Bn/Y mentioned for fans speed 1, this forces the two fans to run in series exactly as they do when commanded to by rad temp.

Also TA and TB are now closed circuit, allowing 12v down to the compressor clutch. The return from the compressor clutch is routed through the afore mentioned flat 3 pin rad temp plug. It is a Bn/R wire coming to Pin3, which is connected to pin 1 (GND). I just need to check whether this connection is broken at rad temps of 115c - to remove engine load. (will edit when I know).

So finally the AC is running, working at light load, it just sits there churning away - again I don't know if the ECU is making any idle adjustments at this point to compensate for increased load - I SUSPECT not.

As the AC works a bit harder, ie. we have taken inital heat out of the car and now want to pull the temp down further, the pressure in the system builds on the pressure line, screwed into which we have two pressure switches - one the triple switch, the other a square switch which can control fans independantly of rad temp.

At an unkown pressure the need to be switched into speed 2

Square Pressure switch

1 Bn/w
2 NOT USED - CONTACT NOT PRESENT
3 NOT USED - CONTACT NOT PRESENT
4 GND
5 Bn/w
6 Bn/y

This is done by pins 1 and 4 going closed circuit, with pin 1 being teed into the same Bn/w wire that is used by the round rad plug to bring the fans into Speed 2. So giving both fans power via. their onboard resistors.

At a higher pressure Again the fans need to come onto speed 3

Which happens when in addition to 4 and 1 being closed circuit, 4,1,5,6 are all now connected together meaning GND on 1, 5 and 6.

5 switches Green relay in short box, in exactly the same way as for rad temp, so giving rad temp Full power.

6 Switches T85b on the Brown relay in short box, so giving the AC fan full power.



Coming back to the triple switch, I think there might be a facility to inform the ecu that the AC pressure is extremely high and force the clutch to lose signal and thus disengage the AC until the pressure falls again.
And Suspect the final wire is to inform the ECU to give the IACV more steps at idle to cover the increased load, ie. the ECU is forewarned about this, rather than the IACV having to adjust quite a few steps the first time idle conditions are used which may result in a stall.

I have yet to find out whether my simtec 56.5 ecu will be plug and play with AC functions, I blooming hope so. If not the majority of it could be done with a few relays ie. minimum pressure check, high pressure cut out, just the IACV adjustment would be difficult - assuming I'm right about that.

Please inform me of any further info, or edits that could be made to aid ease of reading. All info refers to a x20xev engined car, 1997 LS spec.