L337TurboZ

iTrader: (1)

Just installed my new MS3PNP for my 1990 1.6. Everything seems to be working fine except the A/C. When I turn on the A/C it will kick the idle up and turn on the fan. It is not activating the compressor. If I splice the Output (L/B) wire with the Input (Lt G/B) wire the A/C compressor will come on and the MS kicks the idle up/turns fan on. A/C blowing cold, system is properly charged.

I know that the AC switch shoud have 0 volts when On because it is grounding the relay and 12 when Off cause the circuit is open. Used a test lamp to check for the MS system sending power to ground at the L/B output. Nothing. So I have two ideas of what's wrong, either the unit they made has an issue or my settings aren't right. Maybe it is just how it is supposed to be wired up for MS.

I'm fairly certain that it shouldn't operate like that. The idle is ok but it isn't properly controlling compressor delay meaning it will stall the car on some A/C initial operation. I called DIY and they werent really helpful. Explained everything and the guy didn't have much to say. If anyone can give me some info on why it
may possibly not be working it would be a big help. I'm attaching a screen shot of the current A/C idle settings in TS.

cpierr03

Oh look, something I can actually answer.

Inj J triggers the A/C compressor, Inj I triggers the condenser fan. You have to set the Idle-Up output to Inj J

This is how I'm triggering the condenser fan:


Note this is on an NA8 so may be different for you.

L337TurboZ

iTrader: (1)

Awesome! I will change the settings in the morning and report back.

L337TurboZ

iTrader: (1)

Got everything squared away. Setting it to the correct output made a difference. Not sure if I had fat fingered it when using a touch screen or if that was how it was on the initial map they sent me

cpierr03

Mine was set incorrectly in my base map as well.

I spent an entire day troubleshooting every mechanical aspect of my A/C system before I starting pulsing outputs on Megasquirt to figure it out.

Tahzi

Hi guys, I signed up just to say this. My compressor was not turning on, but everything else was fine - the relays and wiring harness. I even ended up replacing the them just because and all I did was switch my Int I to Int J and it works! Finally got my cold AC again. Thanks cpierr03!!