Vitara Aircon Switching Off And On

[cheeryble]

Hi

Suzuki Vitara 1999, the older, but very much loved by all owners, squarer shaped model.

LAst year I had some problems, windows and aircon.

A window wasn't working and the aircon after some erratic not working, had given up.

I gave it to Suzuki but it seems electrical problems are difficult to get sorted in Thailand, and it took a week or more to get it back.

everything OK for a half year or year, now I have two windows not working, but I'm here today to ask about the aircon.

This is now stopping working for hours or days, very unreliable and very much missed.

Background:

Aircon either works as normal or doesn't work, no in between.

Fan switch seems OK 1, 2 and 3 work IF the aircon is still working.

A little cool air still seems to drift out of the aircon grille if it's not working.

YESTERDAY I MAY repeat MAY have got a clue:

The air had not worked for a day, but I parked it in hot sun and it got baking inside.

When I started up air worked as normal.

Presumably there is a thermostat measuring the internal air temperature to switch the air on and off as appropriate? (I'm not sure of this as it always seems to be ON in Thailand)

It occurred to me this MAY be to do with a thermostat and the extra high temperature had tripped it to ON.

This would fit with the air either working or NOT working.....no half way.

My question:

Where is the air thermostat situated?

Presumably this thermostat could simply be shorted for permanent on.

Any further ideas?

Edited May 17, 2013 by cheeryble

[Jitar]

I don't know the Suzuki AC system but most older cars did not have a thermostat, apart from a few upmarket climate control types. The temperature control on the dash usually adjusts mixing of cool and warm air.

If the AC is cool sometimes and not others it may not be an easy fix and you are probably going to need a AC shop to check it. If the compressor clutch kicks in when the AC is turned on but the system is not cooling it could be the TX or expansion valve sticking or partially blocked dryer. If it cools sometime or on start-up but stops after a while, it might be icing up.

[Ace of Pop]

What area are are you in.?.

[cheeryble]

I don't know the Suzuki AC system but most older cars did not have a thermostat, apart from a few upmarket climate control types. The temperature control on the dash usually adjusts mixing of cool and warm air.

If the AC is cool sometimes and not others it may not be an easy fix and you are probably going to need a AC shop to check it. If the compressor clutch kicks in when the AC is turned on but the system is not cooling it could be the TX or expansion valve sticking or partially blocked dryer. If it cools sometime or on start-up but stops after a while, it might be icing up.

Thanks Jitar

Situation is it either works (including fan) or does not (in which case no fan).

[cheeryble]

What area are are you in.?.

Chiangmai.
When can you come round? Edited May 17, 2013 by cheeryble

[Jitar]

I don't know the Suzuki AC system but most older cars did not have a thermostat, apart from a few upmarket climate control types. The temperature control on the dash usually adjusts mixing of cool and warm air.

If the AC is cool sometimes and not others it may not be an easy fix and you are probably going to need a AC shop to check it. If the compressor clutch kicks in when the AC is turned on but the system is not cooling it could be the TX or expansion valve sticking or partially blocked dryer. If it cools sometime or on start-up but stops after a while, it might be icing up.

Thanks Jitar

Situation is it either works (including fan) or does not (in which case no fan).

The fan should work regardless of the AC. If the fan does not work some times, it might just be a bad connection in the fan wiring or switch.

[cheeryble]

The fan should work regardless of the AC. If the fan does not work some times, it might just be a bad connection in the fan wiring or switch.

You have a good point.

Kinda don't quite know how the sensors work in aircon, but might this fit with a hint of cold air drizzling out of the aircon vents.

In other words I wouldn't have thought the aircon....the down in the engine parts.....could work without the fan on.......but maybe it can?

[Ace of Pop]

Cant help U with a good A.C. Shop in C.M. Wifes friend has same Suzi,nice vehicle.10 Years and looks like new.

[cheeryble]

Clue clue!

even if the fans are not blowing, when I click the button switch for AIR ON the the engine speed goes up a little.

When I switch it OFF there is a little click audible from somewhere like in the engine.

This, along with the cool air drizzling out of the vents, suggests to me that Jitar is right and the problem is somewhere in the fan circuit.

BTW ....when it's all working......if one turns the fan down to 0, the air switches off too, visible by the air button light going off.

However it seems this system is not working when the problem starts, as the air system in the engine compartment is working, just not being blown into the cab.

Edited May 18, 2013 by cheeryble

[sotsira]

Yes, it sounds like the air con system is working fine mechanically but the fan motor is

losing it's electrical feed preventing the cooled air entering the interior.

This type of fault is diagnosed with more ease when the fault is apparent,

but check all your connecting plugs and wiring for loose or dirty connections in the circuit.

Also check the fuse and relay for the fan motor that they have a good clean connection in the fuse box.

Remember that Intermittent faults could be just a loose or corroded (dirty) connection anywhere in the circuit.

[cheeryble]

Thankyou Sotsira.

The strange thing is the fan is either working 0% or 100% ........there is no in between as one might get from a poor connection.

On thinking......maybe there could be a poor connection in the pre-relay circuit but as long as the really kicks in it has kicked in properly.

Are we sure there's a relay for the fan motor?

[sotsira]

I mentioned the relay because most of the time there is a relay in the fan motor circuit.

However i don't know whether there is one in the Vitara's system, you'll have to check.

A poor connection can cause full operation and no operation intermittently.

As i stated before the problem can be diagnosed much easier when the fan stops working,

for example:

is there a feed at the motor? can you put a direct feed to the motor and see if it operates?

is there a feed at the switch?can you bypass the switch to see if the fan operates?

is there a feed at the fuse or relay?

[cheeryble]

Yes, thanks

The reason I mentioned 0% or 100% would be more accurately be put that it never switches on and off quickly as with a poor connection you know if a lamp had a bad connection it might almost flicker or on/off very short term.

This doesn't seem to happen.

Edited May 19, 2013 by cheeryble

[cheeryble]

OK I started on this seriously today.

To recap:

The fan for the aircon (or just the fan alone) works absolutely fine and strong, at all it's speeds ....UNTIL it doesn't. It will work for a day or two, or an hour or two, then not work for an hour or a day or five days.

I now believe the aircon is OK as the engine speeds up when I turn the aircon on (the little aircon light comes on too) and a sort of click down below when I turn off.

I believe the fan system is the problem.

I just looked again because last night it switched off again.

What I believe is the relevant fuse for the job seems fine.

I then took out the radio/clock section and loosened everything up around the control panel so I could get inside a bit.

I have tried turning on ignition and fan motor to high, then fiddling with all the connectors around the fan speed switch and elsewhere. No go.

I have just now discovered the fan is left side of the passenger footwell.

Fairly easy to get at on the side of the motor part of the fan is a simple two wire connector.

On the fan side of the connector, strangely, both sides say +.

On the car side of the connector two wires come in, happily pink and black.

With the fan on high, I test. I get 12 v between the two.

OK big progress!!

I put the fan switch on high and tapped the motor hard with a hammer........yes the good old hammer......and on came the fan.

So unlikely it's anything but new brushes or at worst new motor needed....I'll take it apart tomorrow.

What I'd like to know is:

When I connect my multimeter probes into the pink and black connector supplying fan motor I get `12.5 v.

But when I turn down the fan switch from high to medium to low, the voltage remains the same....until I switch to 0.

So how does the motor know how to slow down.......clairvoyancy?

[cheeryble]

ps hoping to find a brush is kinda sticking in it's casing which I remember seeing before elsewhere when the brush gets a bit worn down so the spring is exerting less force (though Hooke's Law says should be same force I think that's for a perfect spring of infinite length which one of thee little fellas ain't I'd say.)

Would still love to know why no change in voltage for different fan speeds.

[cheeryble]

Have now learned that whenever the Air fain stops a light tap on the motor which I can reach from the drivers seat is enough to make it go again (for a while......then another tap)

God a bit of knowledge is a wonderful thing, those baking hot days with no air.

[IMHO]

Have now learned that whenever the Air fain stops a light tap on the motor which I can reach from the drivers seat is enough to make it go again (for a while......then another tap)

God a bit of knowledge is a wonderful thing, those baking hot days with no air.

Well, looks like you've found the culprit

[cheeryble]

Well, looks like you've found the culprit

Yeah.....

Not only that I took my driver door apart to see why the window not opening (nit good in the old days when I had no aircon). Checked the motor had 12v when switch pressed.

Guess what I did next.

Yes, the hammer.

Worked immediately.