Please help ==> air conditioning problem

Hi all
I have an air conditioning problem. When a car standstill,there is NO cool air from a/c at all (condenser fan doesn't spin too but a compressor kick in). However, when the car moves at some speed,the a/c is normal there is cool air from a/c. Please give me some advice what I should check at first. Which part is possible in faulty? Anyone has a/c wiring diagram.
My van : diesel engine ,3000 cc. left-hand drive. LH174 series
thanks
worren

At a standstill the ECU may cut the A/C to prevent the engine either overheating or from stalling.

What is the air temperature?

What speed does it tick over at?

Clive wrote:

At a standstill the ECU may cut the A/C to prevent the engine either overheating or from stalling.

What is the air temperature?

What speed does it tick over at?

Thank you Clive to reply my post. Yesterday, I have a look a van as same model as my car and I find something is different. The car standstill ===> When turn on a/c and compressor kicks in, a condenser fan spins.(mine doesn't spin eventhough the compressor kicks in)So, my condenser fan is faulty for sure. Moreover, I suspect why while the compressor kicks in,there is no cool air from a/c. I have no wiring diagram for a/c,so I don't know the condensor fan control circuit. I think while my van is moving,there is some wind flowing pass the condenser,so the heat can dissipate,but while the car standstill when the condenser fan doesn't spin,so the heat can not dissipate.

If the fan does not work the system can overheat and cause $$$$ worth of damage.
Certainly the pressure will be very high.
The fan can be reached through the grille, not a lot of room but can be done, I've done it. Mine was rusted in and I had to break things to remove it.
Just fitted a normal car radiator fan in it's place, secured with cable ties and never had another problem.
The fan was so bad it was a struggle to turn by hand.

If the wiring diagram is not on this site I'd guess you won't find it anywhere.

Clive wrote:

If the fan does not work the system can overheat and cause $$$$ worth of damage.
Certainly the pressure will be very high.
The fan can be reached through the grille, not a lot of room but can be done, I've done it. Mine was rusted in and I had to break things to remove it.
Just fitted a normal car radiator fan in it's place, secured with cable ties and never had another problem.
The fan was so bad it was a struggle to turn by hand.

If the wiring diagram is not on this site I'd guess you won't find it anywhere.

Thanks Clive to reply my post.Anyway,a temperature guage is still normal. It doesn't go higher to the red zone. In case of faulty a condenser fan. Can it cause overheat? There are 2 fan fitted in van,right ? one is for radiator and another one for the condenser.In my case, the radiator fan works normally,while the condenser fan is faulty.Can it cause overheat? At this moment, I have use my car everyday.
thanks
worren

Sorry I mean the A/C overheat not the engine.