2006 Jaguar S Type HVAC.

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2006 Jaguar S Type HVAC.

Postby STC » Wed Aug 23, 2017 10:42 pm

This came to me blowing Hot Air through the vents with no opportunity to switch it to cold - it is a full Climate Control System - Dual Controls for Driver and Passenger.

The previous repairing garage, where he works as a driver, fitted a Condenser, god knows why?? Sent the module away for whatever it is these testers do then have scratched their bottoms for about 6 weeks and palmed it off on me.


The only fault code in the car is B1265 Servo Motor Cold Air Bypass -
Possible Causes: Circuit Failure Climate control module, cold air bypass actuator circuits - Short circuit to ground, short circuit to power, open circuit, high resistance Actuator movement blocked or obstructed Actuator - Internal failure
Repair: Refer to the electrical circuit diagrams and check the cold air bypass actuator circuits for short circuit to ground, short circuit to power, open circuit, high resistance. Repair circuit(s) as required. Check for obstructions that may be impeding the actuator operation and rectify as required. Clear DTC and retest.
If fault persists, check and install a new cold air bypass actuator as required


Instructions from Jaguar Topix using the vehicle VIN in blue above. This car does NOT have a "cold air bypass actuator" its not on the wiring diagram and never been in the car. Period !!!

So we reflash the Climate Control Module as per VM instructions using a licensed factory tool - no change.

What it does have is Duo Valve set up, 2 solenoids sharing a common B+ and individual PWMs from the module. Fixed the broken wire and we now can control Ambient to Hot air coming out of the Vents - Fixed.

Final checks reveal that code "B1265 Servo Motor Cold Air Bypass" will not clear and the Air Con Compressor will not engage

That left me wondering , is that code Paralysing Compressor operation ???

Moving On, tests at the Compressor relay confirm that the Relay can be and is being switched on and off on demand via the button in the cabin. I established that we have another broken wire from Relay 87 to Compressor, found and repaired that to find that the compressor clutch has B- & B+. Apply a hard Earth o B+ and it will pop the fuse. Probe B- and it will trip the 8 amp circuit breaker in the probe. The clutch does not engage. Beating it with a bar did not help or make it twitch. Its ruined.

New Compressor fitted and we have a fix :) :) :) :) A happy man Paid and gone.

However we have come full circle and " B1265 Servo Motor Cold Air Bypass" is still there - the one and only code in this 11 year old beast yet the entire HVAC dances to any demand I make on it.

Why is that code still there making a mockery of my efforts ??? I feel uneasy, afraid to use that money certain yet uncertain that I have fixed it. Not a good place - unnerving !
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Re: 2006 Jaguar S Type HVAC.

Postby RYM6746 » Thu Aug 24, 2017 12:05 am

Hi STC I have very limited info on jags but I had a little poke around online and found this. Not sure if it will help as I am sure you are aware of the BS you can get given but it does make a little sense.

"That B1265 is for the cold air bypass. They used to use an actuator for the blend but since this vehicle has a heater valve this motor is no longer needed. For some reason the module will flag the code but there is no repair needed. Basically the middle yellow pin is hot at all times. Then the module will pulse ground to the other two depending in the temp. We should pinch off the hoses from the valve to the core and see if the air cools."

I wonder if there is a temp sensor picking up that one of those valves isn't shutting properly?
That's all I have got I am afraid
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Re: 2006 Jaguar S Type HVAC.

Postby STC » Thu Aug 24, 2017 10:51 am

RYM

Thanks good information. I can now ignore that code and be confident of the repair.

It seems that this car was born and will die with that fault code. Jaguar Topix, the tos5ers, led me right up the wrong tree, doing module flashing, chasing components that don't exist ... for hours with that. Waste of time and money.

If a horse was that useless one would shoot it. Out of it's misery!
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