mx5cartalk.com

Evening all,

When I bought my NA8A (Nov '93 build) I was aware the air conditioning was not working. So today I spent a few minutes trying to see if there was anything obvious.

1. With 'AC' button depressed, and the fan speed set to 1 or above, the engine revs increase and the passenger side only radiator fan comes on. On my previous NA6 models when the AC is engaged both radiator fans will spin up.

2. The belt pully on the front of the air conditioning compressor rotates, without, or without the AC engaged. However the compressor does not appear to be engaged, i.e the compressor is not rotating with the belt pulley.

Could the compressor be seized, or (assuming there is an electric clutch) the AC compressor clutch is not being engaged?

All thoughts would be appreciated.

The MX5 aircon is a clutch type unit and only engages when you turn the air con on. It its seized it will make horrible noises.

Only one fan is supposed to come on AFAIK. If your problem is that the aircon is not getting cold, you most likely don't have an refrigerant left and will need a regas..

The NA8 A/C fan Is controled by the ECU. As is the A/C Clutch
there is a low pressure switch in the A/C System that cuts out the A/C Input request to the ECU.
No Input request means to A/C clutch or A/C Fan

On the NA6 it was all done under the bonnet buy one relay
the comupter just got told to raise the idle

Russell

Recently purchased a 200K NB8a and the seller supplied me with a repalcemnet AC compressor as the clutch was cactus

The AC had worked but the electric clutch was beyind repair and becoming dangerous, I Treid to replace the clutch only today, failing as the bearing mount was worn beyond use.

I ended up replaced the full compressor, it is not currently gassed, i have no AC working and no fans, It could be the low pressure signal to the ecu that causes the ac clutch to not engaging or the ac fan not coming on
but i now have the issue of no fans coming on at all so the idle fan is not working either is this and ECU issue as well

Should i disconnect the battery Over night and hope the ecu resets the fans