96 brake light switch - tested everything, what next?

[fireant]

Hello,

Today I experienced the dreaded problem of not being able to shift out of park and no tail lights. I had my trailer on at the time.

I managed to get the trailer and truck home by turning it off and then to accessory, then using neutral gear to start from.

So I checked the forums and followed all the leads I've found so far, but I still havent got it nailed down.. can you help?

What I've done:

1. Replaced the #10 brake interconnect fuse (7.5A)
2. Cleaned brake pedal switch connections with De-Oxit
3. Removed the trailer lighting harness and reconnected to the factory configuration
4. Removed and tested the brake pedal switch for continuity when pressed - it tests good, so the switch is ok
5. Tried to bridge the connections in the brake pedal switch harness with a wire, but no lights

I dont really know what else to look for... from what I've seen the switch is good and the fuse is good...what's next?

Thanks for reading!

 

[martin]

do these three things and post the results.

ignition off. check for 12v at the brake switch.

ignition at accessory, check for 12v at the brake switch,

ignition at run position, check for 12v at the brake switch.

 

[bigmark303]

Had that same problem on two of mine. Was the neutral safety switch fuse. Check that fuse as well.

 

[AgPete139]

Had that same problem on two of mine. Was the neutral safety switch fuse. Check that fuse as well.

Vehicles equipped with automatic transmissions require the use of a neutral safety switch. The neutral safety switch prevents the engine from being started unless the shift selector of the transmission is in NEUTRAL or PARK. It disables the starting circuit when the transmission is in gear. This safety feature prevents the accidental starting of a vehicle in gear, which can result in personal injury and vehicle damage.

 

[fireant]

I went back to the owners guide to look for a Neutral Safety Switch fuse and didnt find one. It turns out the post-94 automatic models had a mechanical doohickey to do the same job.

HOWEVER, while scanning the fuse diagram I noticed something I had missed before. There's a 15A fuse #13 that has "Stop Lamps" in the label. I had previously looked for "Brake Lights" and was confused by not seeing one.

Sure enough the "Stop Lamps" fuse was blown and after replacing it everything works again.

Thanks everyone for the help... it led me to an answer in a roundabout way, and I'm glad to have learned a little bit about the whole brake signal system now.