My A33 air cond blower stop working suddently

[doraemon98]

My A33 air cond blower stop working suddently (FIXED)

Out of sudden my air cond blower stops working the moment i starts my car in the morning.

Check all the fuse and relay turns out to be OK.

Anyone had this experience before?

 

[weikee]

Power transistor problem, or blower itself.

 

[doraemon98]

Errr any price reference for these 2 parts?

 

[doraemon98]

The culprit is the power transistor. Went to get it replace at Banly auto air cond, located in Jalan Jelutong Penang. BANLY AUTO AIR-COND

This piece of crap cost me RM370!!! Not even original one somemore. Original one got nissan logo on it.

The boss somemore said I am lucky not the blower spoiled. The blower will cost around RM600!!

 

[weikee]

I got mine for RM 50 at chop shop. New one at Sim Gee around 160+-. Not original.

Best is i did not even use it after i brought it. Cause the problem was a copper cable in the cooling coil short my power transistor, that make my power transistor go to high fan speed.

 

[doraemon98]

How can the copper cable shorted, and inside the cooling coil? It should not suppose to be short if no one messed with it.

 

[weikee]

The valve inside the cooling coil have copper, and is ground. Could be during the service of my a/c, the guy bend the copper and nearly touch the heat sink of the power transistor. So after so many months of bump and hump the copper move and short the heat sink loh.

The Power transistor is -ve (ground) trigger. So when it short it go into high speed mode. And sometime it back to normal "after i hit the hump" Make me confuse like the a/c ecu got problem or loose connector. Lucky is just a short problem.

 

[doraemon98]

Ok, got back at home... strip the power transistor module open.

The circuit is rather simple and straight forward. Finally got the culprit. It was TCO (Temperature cut off) that is faulty.

The TCO is mount on top of the MOSFET.

This is the TCO. Original spec was 2A, 140 Celsius. I unable to get the same spec in electronic shop. So, i got 2A, 110 Celsius. Cost only RM2.00.

After solder everything together, tested on the car and whola! It just works.

 

[doraemon98]

This morning, something strike my mind by asking why that power transistor module required such a huge heat sink, and need such high temperature rating of TCO.

I immediately remove the power transistor module once i park my car in office. I can feel the heat on the screw surface during unscrewing it. Once remove, i took a grab on the heat sink, and i can feel it is very hot. Its as hot as your dash board that park under the sun for hours. You can only hold it for 5 seconds and the most 10 seconds only.

Is this normal or my blower motor is consume a lot more power than usual?

Sorry I dun hv a equipment to measure the actual temperature.

 

[weikee]

The power transistor do generate lots of heat, that is why is place in the cooling coil. Faulty blower can drain large current from Power transistor too. So you need to do the guessing.

 

[doraemon98]

The power transistor do generate lots of heat, that is why is place in the cooling coil. Faulty blower can drain large current from Power transistor too. So you need to do the guessing.

The power transistor for A33 is placed in between blower motor and cooling coil. Hence the heat disperse by ambient temperature wind. I am not sure yours...

I use amp meter to measure the current draw by the blower, i got approx 10amp in highest speed.

Here is how I measure it. I remove blower motor fuse (located in engine hood), put the meter probe series at the fuse connector. Turn ignition to ON (engine not running), then put the blower to top speed with A/C switch OFF.

Care to share how much current your blower drawn?

 

[weikee]

I never really try measure it. So can't tell. What is the Fuse for the blower? if its 15amp, think 10amp maybe ok.

Not sure if the blower got any watt indicator, If it have how many watt. So can calculate how many Amp it take.

 

[doraemon98]

Ya, there are 2x 15amp fuse parallel to the blower. I dunno why it design this way.