Hello all,,,I am a new user so please bear with me if I make any mistakes.I have read the threads of some people having the same issue as I am experiencing,have done majority of whats been posted ,,,but if you will indulge, let me run the gamete of symptoms.
ABS light is on,stays on, no heater fan ,no electric windows,,,,checked all fuses all good, pulled the circuit breaker that actually controls that circuit,re-set one time everything worked until the next time truck was started,tried re-setting again,again no luck. replaced circuit breaker only to still have no windows,heater fan re-checked all fuses all good,test lighted both terminals in the fuse block that the circuit breaker actually sets in,,,no current at either terminal. Did replace the ignition switch some time ago after they had issues with it. Also have read about/replaced the abs module,still the problem exists,have double checked grounds and even added a extra ground just to satisfy my curiosity about the issue ,,,,any help would be appreciated or new ideas of which I haven't covered

 

I suggest reading the stickies at the top of the new member area

 

*Moved to 'Lighting & Electrical'.*

 

As far as your ABS light goes, what is your brake fluid level? If it's low then it could be causing the light.

 

It is the ignition switch, i put one in this afternoon with the same symptoms ABS light on, No power windows, No heater/AC fan. Blazers are death on ignition switches, sometimes they give these symptoms & sometimes they cause the transmission not to downshift & throw a bunch of electronic transmission torque converter codes. Don't waste your time on these tracing wiring harnesses, buy a switch & put it in.