A/C THERMO

[Dudley007]

Hi ive got a 05 zd30 and the thermo for the AC will not work ive replaced the thermo fan checked all fuses r good and swapped the relay over but still no go i don't know were the ac temp sensor is otherwise I would change it to ive hook yhe fan straight to the battery and it works but not of the ac

 

[Horatius]

Hi ive got a 05 zd30 and the thermo for the AC will not work ive replaced the thermo fan checked all fuses r good and swapped the relay over but still no go i don't know were the ac temp sensor is otherwise I would change it to ive hook yhe fan straight to the battery and it works but not of the ac

Is the compressor actually working? Afaik the condenser fan is supposed to run whenever the compressor is on.

 

[Horatius]

According to the manual there is a "thermo control amp" module that works with a thermistor to turn the compressor off when the evaporator starts freezing up (to defrost it). It's in the evaporator or "cooling unit" itself (under the dash).

From the a/c schematic it looks like the condenser fan cct goes battery>fuse>cooling fan relay>fan. The relay is switched via a pressure switch ("triple pressure switch") on top of the liquid tank (small silver cannister front driver's side). So the fan won't run if the compressor isn't going, or if there is lack of refrigerant/pressure. If you've checked the fuses and changed the relay, the problem might be lack of pressure in the system.

 

[Dudley007]

According to the manual there is a "thermo control amp" module that works with a thermistor to turn the compressor off when the evaporator starts freezing up (to defrost it). It's in the evaporator or "cooling unit" itself (under the dash).

From the a/c schematic it looks like the condenser fan cct goes battery>fuse>cooling fan relay>fan. The relay is switched via a pressure switch ("triple pressure switch") on top of the liquid tank (small silver cannister front driver's side). So the fan won't run if the compressor isn't going, or if there is lack of refrigerant/pressure. If you've checked the fuses and changed the relay, the problem might be lack of pressure in the system.

The AC is working and the compressor still kicks in.
I replaced the fan because the outer fan plastic had stripped of the motors shaft and the motor had seized up and now I can't get the fan to come on with rhe AC .
The condenser is getting hot but ill check the other cylinder to to see if the wire is of

 

[Horatius]

From the a/c schematic it looks like the condenser fan cct goes battery>fuse>cooling fan relay>fan.

Gave you a bum steer there, in the "*" it says that cooling fan cct was for an earlier model (QD32). Sorry about that.

There is no diagram in the manual that shows the fan (for zd30) that I can find in the "heating and air conditioning" section. It does show the pressure switch and says it is an input to the ECM for the cooling fan (rather than switching a relay). Afaik in the zd30 the ECM controls that fan. At any rate I just checked mine and it runs with the compressor.

If the fan seized up previously it would probably have blown a fuse trying to run, possibly you missed a fuse somewhere? Either that or the pressure switch is faulty?

 

[Dudley007]

Gave you a bum steer there, in the "*" it says that cooling fan cct was for an earlier model (QD32). Sorry about that.

There is no diagram in the manual that shows the fan (for zd30) that I can find in the "heating and air conditioning" section. It does show the pressure switch and says it is an input to the ECM for the cooling fan (rather than switching a relay). Afaik in the zd30 the ECM controls that fan. At any rate I just checked mine and it runs with the compressor.

If the fan seized up previously it would probably have blown a fuse trying to run, possibly you missed a fuse somewhere? Either that or the pressure switch is faulty?

Im thinking the sensor on the dry air cylinder has had it but I can't change it without letting the gas go as this is the only thing I haven't changed yet

 

[Horatius]

Im thinking the sensor on the dry air cylinder has had it but I can't change it without letting the gas go as this is the only thing I haven't changed yet

Yep, that's the pressure switch on the "liquid tank" according to the manual. Should be a way to test it first.

 

[Horatius]

Here's a link to the manual for the D22.

https://navlife.com.au/d22-series-service-manuals/

 

[Horatius]

Here's the relevant part of the diagram.

Here's the info for the switch. Looks like with a/c running you should have continuity between pins 2-3. If not, either the pressure is too low or the switch is faulty.