bobnubira

Driver's door and fuel door were the only doors that would pneumatically lock and unlock with the key in the door. The other 3 doors and the trunk lid are controlled by a separate vacuum hose from the central locking system air and vacuum pump. Figured there was a hole in one of those lines. However, I took the lines off the pump and tested them separately and they operate the vacuum locks as expected. Turned the pump with the key and only the drivers door and fuel door vacuum nipple produce a vacuum. No vacuum at the other nipple.

Took the pump apart hoping that the vanes were broken and I could get a rebuilt pump for $70 but the graphite vanes were fine. Should have expected this with normal vacuum at one nipple but I thought the pump might have dual vanes but it doesn't.

Looks like there is a solenoid and some type of vacuum gauge on the separate circuit board attached by a ribbon cable to the main electronics board. The solenoid measure 64 ohms but there is a bit of calcium deposits at the top of it and I am wondering if it has mechanically frozen preventing the vacuum from the pump reaching the larger nipple and its vacuum line. Tried a little PB blaster without help. Any one have a fix for this and know how to disassemble it for repair?

bobnubira

Gave up trying to repair the frozen solenoid. Bought a used central locking module with the pump and solenoid and installed it. Worked fine with the key in the driver's door lock but remote key function would not work. Vag-com had directions for programIng a new key but no directions for programming a replacement central locking system module. Therefore I unsoldered the old good circuit board from the 4 conductor ribbon cable and the pump wires and soldered it to the good replacement components. Now remote and keys both work fine.