Power steering and brakes fail when aircon is engaged

[mikey177]

SOS.

My 2002 Kia Carnival is suffering from a weird problem. When I turn the aircon on, the brake and battery warning lights come on and the power steering and brakes cease to function.

Actually, if I keep the steering wheel in a turn for more than a few seconds, the warning indicators also light up, and they go off when the steering wheel is centered again. However, the problem is most noticeable when the aircon is switched on.

The mechanics I consulted diagnosed it to be an alternator problem, but I already had my alternator inspected yesterday. They replaced an IC and re-installed the alternator, but the problem still persisted.

Maybe you guys could shed some light on this predicament I am in. Mahirap magmaneho na walang preno

[Type 100]

That's odd...unless explicitly stated otherwise, the power steering and brake systems are usually hydraulic in nature.

You might be looking in the wrong place as the problem's probably not electrical in nature. Try having your power steering pump, brake lines, brake booster and/or brake master cylinder checked.

I hope this helps.

[mikey177]

^ Your post was providential in getting me to look at the problem from another perspective. Naisip ko din na baka hindi electrical yung cause, kundi symptom lang sya ng underlying problem.

Anyway, I managed to drive the van from Tarlac City to Calasiao and have it checked at Kia Pangasinan. Ayun, camshaft pulley ang may sala, and I saw it with my own two eyes, exactly as yapoy86 explained in the Carnival/Sedona thread:

have your CRANK SHAFT PULLEY checked... possible that the main drive pulley is already separated from the belt pulley.. normally kasi meron "rubber" sa pagitan nung CRANK SHAFT PULLEY that separates the main drive dun sa belt for absorbing vibration... possible na natanggal na yung rubber... your power steering is mechanical so kahit wala kang battery as long as umaandar ang makina eh meron ka dapat power steering assist also your brake assist is mechanical vacuum pump at the back of the alternator.. i'll post the sample pic of that pulley later...same happened to our BESTA before... bigla lang nawalan ng power steering at brake assist.. tapos umilaw yung battery charging indicator.. pag on ng aircon mahina din lamig... yung pulley pala problema umiikot yung crankshaft pulley pero yung mga nakadikit sa kanya like alternator, aircon and power steering pump eh naiiwan kasi nawala na nga yung rubber damper na connector nila..

kaya nag ilaw yung battery charging mo kasi hindi na umiikot yung alternator mo naiiwan na especially pag may load yung belts when you turn the power steering... (alternator and power steering share the same belt) same thing pag nag on ka ng aircon.. yung parking brake lights nag on kasi connected yan sa battery charging indicator try mo na disengage yung parking brake before starting the engine you will notice kahit hindi ka naka parking brake eh naka ilaw pa rin yun.. but once you start it will go away together with the OIL pressure indicator and battery charge indicator.

[Type 100]

Good to hear that. I'm glad the problem's solved now