where is the backup light switch on 1994 chevy express van

 

Your model year or model is wrong.....is it an Express? 96 is the first year.
On the Express. The park neutral position/Transmission range sensor is mounted on the manual shaft on the side of the transmission. right where the cable from the gear shift on the steering column connects.
If your back up lights are not working....I would start at the lights and work back to the tranny. Check your grounds, and test with a test light.....test the wires inside the back of the light housing too.....

 

sorry it,s actually a 2004 expess. I have no power at the light housing, or in the wires where they split to both lights. I cleaned the ground surface and remounted it still no power.

 

are the backup lights controled by the neutral safety switch

 

The park neutral switch is combined with the tranny selection sensor since the tranny is electronic controled. The sensor is conected to the pcm and tells the computer that the tranny is in reverse....
Check the wiring harness at the tranny. Also the tranny shifer cable could not be putting the van into the exact position for the reverse light to come on. Wiggle the gear shift a bit to check.....