Sitting at the lights today, aircon on, idling just under 1000rpm when rpm dropped down to 500rpm briefly then returned to normal but the aircon stopped blowing cold air. Stopped the car at the shops for a hour, got back in aircon going fine again. 20 mins later sitting at the lights rpm drops and aircon stopped working again. Anyone know whats going on?
Sounds like refrig gas is dropping pressure, very common once it warms up. Check the sight glass near the fuel filter for bubbles when the A/C is running, if so you have a leak.
2nded... There is a low pressure switch atop the receiver/dryer which cuts AC compressor when pressure drops too low. I'd get an aircon checkup done. Do a search on here for aircon or A/C for preferred AC repairers in Bris, Pretty sure there was one not too long ago. Might have been CBZX ?
Check the alternator output voltage? Hi Ztoy - I had a similar problem ~3 years back with A/C cutting in/out symtoms like you describe, but in reverse. I would pull up at lights, the A/C would come on again, then after accelerating up to speed and it would cut off and stay off. This behaviour became quite predictable at the time. Eventually we traced the fault to the alternator which had developed a fault causing it to produce a varying output voltage out of the normal operating range. Whenever the voltage went greater than 14.4V (max of the range, I think it was) the computer switched off the A/C system to protect it from damage from overload as was explained to me by the Nissan Service tech guy - pretty clever I thought at the time. Hope this may help you! Regards, MikeB
