I have a 2000 blazer and the 4lo light on the transfer case switch will intermitantly flash and shift into 4lo if I shift into neutral. I have checked and replaced a lot of the vacuum hose. Now I am looking as a switch located in the middle of the firewall (just under the hood) and the vacuum actuator. Any ideas or help would be appreciated before I tear in to this any further.

BTW - with the hose to the vaccum accuator removed from the switch on the firewall the 4 lo light doe sgo out after 30-45 seconds of running.

Thanks in advance,
Bill

 

have you ran the trouble codes on it? Also I never see any harm in taking my cars to a dealer for a diagnostic only $40-50 and they can usually pin point down the problem.

 

I have the same problem, and have no codes set. I have checked the switch wiring, vacuum hoses, and still no answer. Has anyone had a similar problem.

Please help!