1994 Chevy Cheyenne 4wheel drive inop when Brake System War

ROGER EMERICK

MEMBER
1994 CHEVROLET CHEYENNE
6 CYL
4WD
AUTOMATIC
150,000 MILES

I was plowing snow with my truck for ~1/2 hour, when the Brake system warning light came on, and the 4wheel drive (4WD) stopped working. The light went off after about 10 minutes, and 4 wheel drive resumed working. The transmission fluid level appeared normal. Next day I started truck and Brake system warning light stayed on for about 1/2 hour! During this time 4WD did not work. Then light went out and 4WD resumed working. I haven't started it since. Do you know what the problem is? Thank you very much. Roger

3 Replies

KHLOW2008

MECHANIC
41,814 POSTS

Hi Roger,

When brake warning lamp illuminates, the brake fluid level could be low or the sending switch is faulty.

For some models when this happens, it would affect the 4WD.

Was this

answer

helpful?

Yes

No

Wednesday, December 31st, 2008 AT 1:44 PM

ROGER EMERICK

MEMBER
2 POSTS

Turns out it was a short in the ignition switch which caused faulty operation on 1 of the 2 connectors which came off this switch. The connector which did not receive power included 4wd, heater fan, and antilock brakes. Pending correction/replacement of ignition switch, these lines were hot wired to a toggle switch. Thanks for consideration.