2009 Toyota Corolla High Beam flasher issue

[SlickTop Solutions]

So, I'm working on an install for a friend as I have time between other work. The issue is with the high beams on the 2009 Toyota Corolla, it would appear that there is no ground or +12 VDC until you turn the high beams on, so with the high beam switch off, there is no way to turn the bulb on by either adding +12 VDC to the hot, or ground to the Neg wire (confirmed using a power probe).


Currently using a Whelen UHF5150.


Wired correctly:


Black - Ground


Red - Fused power (Battery)


Orange - Console switch


Blue - Left High beam bulb


Blue/White - Left High Beam harness


Yellow - Right High beam bulb


Yellow/White - Right high beam harness


White - Spliced in with Blue/White


White/Black - Spliced in with Orange


Brown - not used


White/Brown - not used


White/Violet - not wired


The flasher activates and the relays click when turned on and the +12 VDC goes on and off with the flasher (verified with power probe). The high beam override works and shuts the flasher off when the high beams are activated and the high beams do come on.


I am thinking that I will have to wire in a full time ground to the ground side of the bulbs (possibly with diodes) to get the high beams to flash.


Just need a few folks to look at this and verify I am thinking the right way (Cajun, C2, anybody)


Thanks.

 

[MESDA6]

If it helps at all, I think the high beams on that car are also DRL's. Not sure how that affects your install, but figured I would mention it in case it's one of those things that is hosing you up on this.

 

[SlickTop Solutions]

If it helps at all, I think the high beams on that car are also DRL's. Not sure how that affects your install, but figured I would mention it in case it's one of those things that is hosing you up on this.

Nope, not DRLs, and no DRLs on this car at all.

 

[shues]

Instead of wiring in a full-time ground, you might be better off wiring in a relay that provides a ground only when the headlight flasher is activated.

 

[SlickTop Solutions]

Instead of wiring in a full-time ground, you might be better off wiring in a relay that provides a ground only when the headlight flasher is activated.

That idea came to me this morning while thinking about it, and will probably be the route I take.


Thanks,


DB

 

[MtnMan]

Sounds like a similar setup to my GM truck: headlight power is positive switched, and low/high beam selection is ground switched. If that's the case, the easy solution is to use a ground switched flasher and keep the headlight switch on when the flasher is in use. Adding a ground relay would be more elegant.

 

[SlickTop Solutions]

Sounds like a similar setup to my GM truck: headlight power is positive switched, and low/high beam selection is ground switched. If that's the case, the easy solution is to use a ground switched flasher and keep the headlight switch on when the flasher is in use. Adding a ground relay would be more elegant.

The flasher I am using can either be pos or neg switched, it doesn't work in either mode.


Nope, no power or ground to the high beams until the high beams are activated, even with the low beams on, there is no power or ground at the high beam. I chased everything back from both high beams and it appears to go to a central lighting module with a couple of relays on it. Both relays activate when the high beams are activated, confirming what I found out with the power probe, no power or ground until the high beams are activated.


Looks like the flasher activated relay for ground it is. And you are right, much more elegant.

 

[SlickTop Solutions]

Instead of wiring in a full-time ground, you might be better off wiring in a relay that provides a ground only when the headlight flasher is activated.

Finished everything up today, relay to activate/provide ground to high beams when flasher activated worked like a champ.

 

[shues]

Finished everything up today, relay to activate/provide ground to high beams when flasher activated worked like a champ.

Excellent!