Again, I'm looking into fixing a friends 1991 Volvo 740 Turbo. He says that the A/C works sometimes. But all of a sudden, the radio will start buzzing and the A/C quits. He can roll down the window which gets the radio to stop buzzing and then the A/C starts working again.

I read that these cars have bad wiring and the heat starts melting the insulation? Is there any key areas that this happens either inside the car or engine bay that I can examine and possibly electrical tape back to life?

Thanks a lot!

anyone? :grin:

you heard correct about the insulation melting, this is in the engine bay only with the heat extremes. It sounds like a really weird problem...

you open the window and the buzzing disapears. What happens when you stop opening the window, eg wind it down and leave it? is this when it stops?

If wires were shorting out, you would have blown fuses. from memory the fuse panel is infront of the gearstick under the ash try in the 740 ... on the ash try base there should be a sticker detailing which fuses are for what function in the car, that should give you a clear idea of which to check.

If you do find a blown fuse, replace it and try again, if it blows then inspect the wiring in the engien bay and look for borken insulation, signs of shorting out on metal etc.... espcially by the compressor around the engine head and where the wires connect into plugs etc... and where they enter the bulk head.

few thigns there to contemplate. post back..

Matt