Hi whining when a/c is on/code125

[zander5]

1996 g voyager, when the a/c is on I hear a whin when speeding up, than after it shifts to overdrivethe whin goes away. If I speed up the whin return and drops out after a certain rpm.

What is code 125, I tryed the key off and on 3 times, 1 flash paused, 2 flashes,paused, 5 flashes. thankyou

[yogi_123rd]

Your codes are actually 12 anf 55. In 1996, all diagnostics were standardized with ODBII codes which are four digits and require a scanner tool to retrieve. Since the on-off-on technic of retrieving codes thru the CES light is still working in your year, you are getting the legacy codes in two digit format. The codes are listed at:

(1980-1995) http://www.allpar.com/fix/80s-codes.html

12: Battery recently disconnect (informational)
55: end of list

As to the whine noise: If the noise only appears when the AC is turned on, it is most likely the compressor bearing starting to go or oil in the AC system is low. The parts stores sell cans of R134 with oil and cans with just oil which you can try adding to the AC system.

The other possibility is a loose/worn compressor belt, but a loose belt tends to high pitch squeal rather than whine. If that's the case, the belt can be tightened or replaced.