So,
I noticed the other day my heater was not working, began searching and found things like, do a backflush, check the pump, check the valve,
i have not got to that yet,
but i did just run the Diag on the climate control unit.
I came up with these errors.

12 - ambient temp sensor
23 - refrigerant dual pressure switch
41 - left fresh/recirc servo
45 - centre vent servo

now i did notice that the ambient temp was not giving me a reading, but i did not notice any other issues with the AC.
it seems to go cold and blow through all vents.
where would be the best place to start looking at these things?

 

23 / Ambient temp sensor is located in the left front brake cooling duct and the connector can get dirty from the environment it is in

The sensor is a thermister which responds oppisite a old school thermocouple

The cabin temp sensor located as a vent hole to the lower left of your steering column can get clogged with dust and is a thermistor also

Clean only with a brush and air as you want to leave the lubricant in place for the sensor mini fan bearings

With a 9 volt battery you can drive the servos back and forth and if you have good ears you can hear them one at a time

With the chance you have worn brushes in the heater coolant pump worn you can bang on it with a broom handle and get the brushes to come loose and make better contact to spin again

The brushes can be changed yourself very cheaply

 

s i realised my ambient temp sensor is not working because it is not there.....
ordering a replacement....
i think the heater may not be working due to a busted thermostat.
not sure but i have noticed the car never quite reaches N (the middle of the guage) whilst driving.
it only reaches to just below.
i have read that it is common for the thermostats to get stuck open and therefore not allow the car to warm up properly and not allow the heater pump to engage.
so i will start there....

 

Motorcarman posted the TSB's (there are several) for addressing heater problems. search his posts for "heater" and you will likely find a thread with all of them in one spot.
T-stat is an excellent starting point. - And can be changed with very little fluid loss. THROW AWAY THE O Ring that comes with your new T-STat!!! Otherwise, you'll soon be shopping the Pick-n-Pulls for a T-stat elbow.

 

No O - ring on thermostat

The electric heater pump motor running is not dependent on the fluid temp

A water solenoid will open and close modulating the coolant flow only for the cabin heat path. this maintains your target cabin temp setting

If the electric cabin heater pump is not turning if you have a high engine RPM you will gets some cabin heater path flow so this can throw you off

 

will hopefully get around to replacing the thermostat in a couple days, then if the heater still doesn't work i will look at the motor bushes,
when i replaced the ambient temp sensor the other week and cleared the error codes, all the other codes have also vanished and not come back. i can only assume that the issues with the servos, are either A, an intermittent issue, or B, and issue that was previously resolved but the errors were not cleared.
either way, one step closer.

 

Bear in mind the temperature gauge, like the oil pressure gauge, is designed to adopt a single central position as long as the underlying readings fall within an acceptable range. In other words, temperature can go up or down without affecting the reading on the gauge, as long as the temperature falls within a specified range. Apparently a not uncommon approach to reducing customer warranty claims, if a little unhelpful to those of us who are actually interested in what is going on!
My temperature gauge settles just below the middle, while oil pressure is dead centre and never moves.

 

true. Just from my experience and what i have seen before i would expect it to climb to just above half, then the thermostat open and for it to drop just below half.
but i an only new to jags and learning the little things bout how it works