Air Conditioning electrical fault problem

[bongo&4kids]

Hi guys,

I got round to getting my Air Con looked at this morning, after focusing on some other more urgent jobs, and it seems that the system is working and holding gas, but there is an electrical fault somewhere in the system which means the compressor is not coming on when turning the air-con on, from the dash.

Does anyone have any advice or experience with this?
What things are there that I could check myself? or if I get a professional to try to fix it, where is the best place to go?

I used one of the mobile services, and this is what he did to identify the situation:

1) Check pressure / Gas level - EMPTY, NO GAS
2) Visual inspection under hood, and underneath vehicle - OK
3) Vacuum test, to determine if system is holding or leaking gas - OK
4) Attempt re-gas and check to see if air-con is working - NOT WORKING
5) Test power at compressor - NO POWER
6) Checked pressure switch (by temporarily bypassing it) - OK
7) Second attempt to re-gas, by attaching cable directly to compressor, from battery,
8. Test again after second re-gas attempt (with cable still directly attached to compressor from battery) - AIR-CON WORKING

So his conclusion is that the air-con system and compressor, are working, but there is an electrical fault somewhere between the dash controls and the compressor, and that I may need an electrician to investigate if there is not a simpler solution.

Any ideas?
Could it be a fuse? damaged wiring?

THANKS!

[bongo&4kids]

Forgot to say that mine is a 95 diesel auto.

[g8dhe]

Which type of controls do you have ? Electronic or manual version of Air Con?

Electronic type

Manual type

[bongo&4kids]

Its the manual type controls with the sliding knobs.

[bongo&4kids]

Thanks,

Any ideas how to make sense of the diagram?

[Northern Bongolow]

just below the glove box door on the passy side there is a really small (1 inch square) grill cut into the facia, this may have a sensor behind it, it senses the cabin temp if its not full of fluff, it has a little fan on it, it may need a good clean out if fitted.
it must be something weird if an aircon guy cannot fix it, hes done the usual stuff like shorting out the front sensor.

[bongo&4kids]

I think I found the grill under the glovebox, but can't see that there is anything behind it - no fan or sensor, as far as I can tell ?

[mikeonb4c]

Don't think Bongos (like mine) with manual systems have any sensors, just the on/off button. I'd imagine it'll be a case of seeing if it works once you find what it is that needs power and find a way to get power to it. Bit surprised the a/c engineer didn't have a bit more advice to offer

Whereabouts are you, in case there's a nearby Bongo specialist we might recommend. In Sussex one name that comes up is County Cars, near Brighton I think.

[bongo&4kids]

When the engineer ran the power directly from the battery to the compressor, the air-con worked ok, and he did manage to re-gas it that way.

But when I activate the air con on the dash, it is just blowing warm air, not cooling.

When the engineer tested the wire going to the compressor with a power meter, it gave no reading, so his conclusion was an electrical fault somewhere, meaning no power is getting to the compressor, and no cold air.

[mikeonb4c]

When the engineer ran the power directly from the battery to the compressor, the air-con worked ok, and he did manage to re-gas it that way.

But when I activate the air con on the dash, it is just blowing warm air, not cooling.

When the engineer tested the wire going to the compressor with a power meter, it gave no reading, so his conclusion was an electrical fault somewhere, meaning no power is getting to the compressor, and no cold air.

Sorry, should have read your original post more clearly. And apologies to the Aircon man. Sounds like you have an electrical supply problem then in switch, wiring or fuse (blown - but why). Shouldn't be too hard to track with help from a sparkle.

[teenmal]

I think I found the grill under the glovebox, but can't see that there is anything behind it - no fan or sensor, as far as I can tell ?

The manual Air Con system does not have a cabin sensor (no need for it ) as it has You

[mikeonb4c]

I think I found the grill under the glovebox, but can't see that there is anything behind it - no fan or sensor, as far as I can tell ?

The manual Air Con system does not have a cabin sensor (no need for it ) as it has You

And that's an excellent point: one less ageing component to go wrong, and I often wonder if the sensor can really judge better than the occupants when they might like aircon on (demisting in winter, for example).

[bongo&4kids]

Ok, so I took the Bongo out for a long drive at the weekend and tested the air-con.

It definitely seems to be blowing much colder than before, so I am wondering if I have some kind of intermittent power problem?

I also noticed that the air-con / heater seems to be on all the time, at a low setting, even when the A/C button is not pressed, and when the fan is off. (I didn't notice this before, as it was left in the de-mist setting, rather the forward air vents).

Does this make any sense to anyone ?!

THANKS!

[mikeonb4c]

Ok, so I took the Bongo out for a long drive at the weekend and tested the air-con.

It definitely seems to be blowing much colder than before, so I am wondering if I have some kind of intermittent power problem?

I also noticed that the air-con / heater seems to be on all the time, at a low setting, even when the A/C button is not pressed, and when the fan is off. (I didn't notice this before, as it was left in the de-mist setting, rather the forward air vents).

Does this make any sense to anyone ?!

THANKS!

Is it perhaps a problem with the blower fan that you have, rather than the Aircon? Is the blower fan working at all 4 speeds? There is no low setting with manual aircon- it is either on (when the Aircon button is pressed in and a faint green light in the switch should be seen) or it is off.

[bongo&4kids]

Yes the blower fan is working on all four speeds.