Thought It Was Neutral Safety Switch Prob... ?

jball · August 5, 2009

I have an 03 Sierra 2500, 64500 miles on it... was driving around last night, parked it and shut it off for a matter of minutes and when i came back to start it there was absolutely no crank or anything, shift indicator shows that it's in 2nd gear, even though shifter is in park position.... bought a new neutral shift switch, installed it with tranny in neutral position like it calls for and still nothing. thought maybe disconnect the battery for a while to let the computer reset, still nothing... took the neutral shift switch off the linkage while still plugged into the electrical leads, turned the inner ring with a pocket knife and the shift indicator never left 2nd gear position....... what gives???? any ideas? Thanks in advance guys!

bill190 · August 5, 2009

Lots of computers involved with all this, so first be sure all those computers have power...

Check fuses to everything! Your owner's manual should give locations of all "fuse boxes".

How to check fuses...

http://www.dinosaurelectronics.com/Test_Fuse.htm

Also check your battery voltage. Should be 12 something volts with the ignition on and not started (a load placed on the battery). (Computers like it around 12 volts.)

If that all checks ok, check the voltage inside the vehicle like from the cigarette lighter center connection to ground. Should be close to what the battery is reading.

If that checks OK, then "hit the books" (GM Factory Service Manual set). Start reading which computer modules are associated with this and then check each module to be sure it has power.

Then check the wiring to the park neutral switch. Check grounds.