Hino 268 No Brake Lights

MIA Hino

Rookie Expediter
Owner/Operator
Hello all,

First post but thanks to this forum I've been able to fix my truck in the past.

I have a 2006 Hino 268 with air brakes which currently the brake lights stopped working.

The lights themselves are functional as well as the wiring going to them but they are not receiving 12 volts. There is however a small voltage jump when the brake pedal is pressed, it jumps from approx. 0.020 volts to 0.300 volts.

I've tested for continuity from each of the taillight's brake light wire to the bulk connector located on the right side of the chassis. The one that's located before the cab. There was continuity on both sides of the connector.

I've tested and adjusted the brake switch at the pedal and all seems well there.I've tested each and every fuse in both boxes and all were functional.

I connected Hino DX2 and live monitered the "stop lamp switch" and "brake switch 1." Only the stop lamp switch showed on when the brake pedal was pressed.

With what the diagnostic showed I went to inspect the service air brake valve switch by the rear axle. Not 100% sure which one it is so I've attached a photo of the two connectors I checked. Visually the terminals and wires were perfect. I then jumped each switch, each individually, and pressed the brake pedal. The brake lights still did not turn on.

An help would be greatly appreciated, I'm willing to try anything.

Happy Thanksgiving!
 

Attachments

  • Screenshot_20221124-184020.jpg
    Screenshot_20221124-184020.jpg
    1.5 MB · Views: 5

greasytshirt

Moderator
Staff member
Mechanic
The valve mounted switch you're after has a black and a white/black wire. It grounds the control side of the stop lamp relay.
Inspect the connector and several inches of its wire for corrosion and cracked insulation. I've seen both.

The stop/turn controller ultimately turns on the brake lights. The red/white wire is the left light, yellow is the right.

The stop lamp relay is behind the fuse box cover amongst the ecus. It has two white blue wires, a red, and a white black.
Grounding the white black should turn on the brake lights.
 

MIA Hino

Rookie Expediter
Owner/Operator
The valve mounted switch you're after has a black and a white/black wire. It grounds the control side of the stop lamp relay.
Inspect the connector and several inches of its wire for corrosion and cracked insulation. I've seen both.

The stop/turn controller ultimately turns on the brake lights. The red/white wire is the left light, yellow is the right.

The stop lamp relay is behind the fuse box cover amongst the ecus. It has two white blue wires, a red, and a white black.
Grounding the white black should turn on the brake lights.
Thank you very much for the help. The problem was infact the stop lamp relay. When I unplugged and opened it there was a lot of corrosion inside. Thankfully dealer had it in stock and was able to swap it out easily. Thanks again.
 

greasytshirt

Moderator
Staff member
Mechanic
Good eye. Many of these relays are common to Toyotas so you can probably get them at Napa. I think the denso part numbers will cross.
 
Top