LMA1973

Okay-the more i have searched, the more confused i have become.

The 2 fans at the front of an ML430 are fans for the AC compressor. Mine are not coming on. Fuse #44 is fine. Compressor doesnt sound like its engaging but i have no idea where its located to see. Which pulley?


Ive seen posts where they say if R134 is low, then compressor wont engage to keep from burnig it up. Ive seen posts where it says compressor will engage regardless. Which is true?

If AC is warm, the two fans in the front arent turning, the compressor isant engaging, then ive got real issues?

sosh

Fans should come on when compressor is engaged. Compressor will not engage when freon/R134 is low. If its low you have a leak. Should be refilled and leak checked. Summer is coming!

boardboy330

If you have a bad leak...the freon would seep out and not let the unit engage. However...when I turned my unit on today (blowing hot air) it did engage. The bottle I used specifically said pump half the bottle in IF the unit doesnt engage and try again to get a pressure reading. I would do that myself. $30 bottle of coolant is cheaper than dealer charging you a few hundred to tell you its broken...only my opinion.

LMA1973

Where is the high pressure port located? I found the low pressure port near the firewall passneger side.

derf0069

any word? I'm having the same issue. I just bought mine, fuse is good. I was able to get the fans to run once as well as the conenser.

LMA1973

I took it to the indy shop and had them do an AC evacuation, leak test, then recharge and the fans fired right up. They wont come on if you are low on refrigerant.