Does anyone here knows how to wire the stop/brake lamps when the RWAL module is missing? The simpler the better, but the turn signals still must work. I'm using the 1993 PCM, the stock brake switch and the wire harness, minus the RWAL module and speed/cruise control and, RWAL wiring to the rear cutoff.

I'm having a hard time figuring this out because the brake switch wires go to the RWAL, speed/cruise control, TS/Haz switch; none of them go to the stop lights directly.

 

they pass thru the turn signal switch after the brake switch, the rwal is a separate circuit from the tail/brake lights, do you have access to a schematic?

 

Removing the rwal module should not effect the tail/ stop lamps. The wire from the brake switch goes to the turn signal switch, through the switch, than back to the brake lights.

 

18ga black/yellow stripe=tail
18ga dark green/yellow=stop left
18ga brown/yellow=stop right
18ga violet/black=reverse
18ga grey=ground

 

True,

my rwal module wire to the valve was unplugged the entire time I've owned the truck, and I never knew it.... yet the brake lights still worked.



I've found that (on my truck) the brake light wiring rots away from the rear connecting harness just behind the Rear passenger tire, up in the frame. That disconnect rearwards wiring was eaten toast on my truck, or at least the wire to the stop / tail was. I removed the connector, wired the tail stop direct with new wire, up to two brand new sockets (which were also gone), and the tail lights work perfectly now.

I'd check those disconnects first, just to see if they're not passing power beyond to the rear tail light harness.

 

With the brake switch from the 93 installed, my turn signal, tail, and backup lights all work, except the brake lights. I have the wiring diagram in the FSM and I know the brake switch feeds the turn/hazard multifunction switch as well as the brake sense in the PCM, RWAL and the speed control.

The brake lights worked in the donor vehicle; but in the receiving vehicle I literally cutoff/tape the wire harness to the RWAL module (right side of the wiring harness under the inst panel) and also literally cutoff/tape the wires going to the rear RWAL sensors. The only wires from the front harness that I extended to the rear are the tail (bk/yl), left/stop (DG/RD), right/stop(BR/RD), backup(VT/BK), and ground (BK)wires. The wire colors change a bit after they go through the intermediate connectors to the rear harness.

Still brake lights don't work. The funny thing is the light above the message center stays on and turns off when I step on the brake pedal :-)

if all else fail i may have to re-solder all the cut rwal and speed sensor wires.