'98 V70 MCC Air Conditioning Relay Not Engaging

[bmdubya1198]

Huh, that’s odd. I’ll check the PN tomorrow.

[ddegner]

It sounds like we have the exact same problem. Basically my MCC ECU either isn't working or was switched before I bought that car and is actually a ACC ECU.

Is there any chance you could tell me the numbers on your ECU or send a photo of the top of it with all the numbers?

Did you have any luck finding other MCC ECUs?

[bmdubya1198]

It sounds like we have the exact same problem. Basically my MCC ECU either isn't working or was switched before I bought that car and is actually a ACC ECU.

Is there any chance you could tell me the numbers on your ECU or send a photo of the top of it with all the numbers?

Did you have any luck finding other MCC ECUs?

You’ll know if it’s an ECC unit, because it has the slider for blower speed.

Unfortunately I was never able to get the part number since this was a customer car and I wasn’t able to track down an MCC unit for him.

[ddegner]

I am having problems diagnosing a 98 MCC AC.

Is there a difference between and ECU/ECM for a MCC or ECC car? I've tried 6 ECUs and none of them have gotten the AC to work, but my mechanic tried one ECU that is from an older turbo and the AC works. The Volvo store says there is no difference.

Thanks

[Chuck W]

Have you checked the high-pressure switch? (Behind the PS headlight?) That was an issue on the wife's '97 last season.

[bmdubya1198]

What ECU are you changing? The actual ECU for the engine, or are you referring to the ECC/MCC unit?

[MRZero]

Anyone know where the RELAY is for the ac/heater blower motor on a 2001 v70xc? All lights turn on and fan indicator light adjust, but the fan never blows/turns on
New motor and resister replaced about 1year ago

Thx