2003 Hilux Hazard switch modification

The right hand directional signal stopped working on my 2003 Hilux, so started looking for the problem. Checked everything and found that the hazard switch was the culprit. With the switch removed and jumper wires installed to simulate being in the flasher "OFF" mode, the RH turn signal began to work.

My truck is fitted with a dual-fuel conversion (gasoline or compressed natural gas). The location of the gas/CNG selector switch and fuel level indicator (lower left hand side of the dash) was hard to see. The hazard switch cutout was a much better location. The rear window defogger switch cutout was a perfect location for a new hazard switch

A factory replacement hazard switch costs 285,000 Colombian pesos (about $95 USD). Being a cheap-ass, I decided to replace the stock switch with an on/off switch and a relay.

After checking out the Hilux Hazard switch circuit, it looked like a 4PDT relay would work.

The parts:

switch.jpg (9.71 KiB) Viewed 8 times
1.) SPST red hazard switch w/led (Ebay - $4.95/free ship)
2.) 1N4001 diode
3.) 4 pole double-throw relay with 12v coil
4.) Hookup wire and double-sided sticky tape.
5.) 1/8” male solderless connectors

Drew up a connecting diagram.

I wanted to retain the original hazard switch plug and not have to cut up the factory wiring harness. Soldered wires to the contacts on the original hazard switch and used it as a jack to connect to the plug on the harness.

The completed relay and jack assembly.

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Installed on the rear of the dash panel

The final installation.

The CNG/Gasoline selector installed in the original hazard switch location below the clock, and the new hazard switch in the rear defogger location.

I looked at a Gen 1 Tacoma schematic because the 1998 Taco and the 2003 Hilux have exactly the same dashboard. The Tacoma switch layout was different, but the circuit was the same. So, I believe this mod could be applied to a Tacoma too.

This was an easy mod and it worked perfectly. I put the relay and the switch assembly together on my bench, and installing it was simply a matter of enlarging the switch cutout slightly and plugging in everything. Total cost was $24,000 COP (about 8 USD.) Project took about 3 days start to finish. Well worth the time.

- JAMES
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