2008 Daytime running lights questions

[foghorn]

Hello, I am new to this forum and have run into a problem with the wife's 2008 Rav4 limited (v6). The DRL's do not come on. Low beams and high beams function properly. Parking brake fully released and no DRL's

1) Do the DRL's operate off the high beams ( at a reduced voltage)?
2) Where are the relays located for the DRL's ?

Any suggestions on where to begin. I hate the idea of taking this into the dealer for something that is probably minor.

[veliksam]

Question 1: yes, they are the same bulb as the high bean and work at a reduced voltage.

Question 2: the relay is located in the fuse/relay box under the hood on the passenger side, mine was a brown one with 5 pins. Maybe your relay is bad?

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[foghorn]

thanks for the help . I went back to the car and played with the brake lever. Seems it was not totally disengaging and allowing the switch contacts to open or close. After a few tries, it seems to be working OK now.

[ravenuer]

Originally Posted by foghorn

thanks for the help . I went back to the car and played with the brake lever. Seems it was not totally disengaging and allowing the switch contacts to open or close. After a few tries, it seems to be working OK now.

Hmmmm, I'd take this opportunity to make durn sure the parking brake is actually releasing completely.

[Carnivore]

I'm having the same problem coincidentally. Mine seemed to stop working right after i had some minor body work done on the rear door area. The body shop guy claims he didn't disconnect the battery but i lost all my radio presets (but not the satellite receiver presets) so i know there was at least some kind of power loss. I was wondering if they somehow wiped the DRL programming from the computer and if so, how to get it back.

Meanwhile i will check the parking brake connection. What did you do, just jiggle the handle? My dashboard brake light goes out when i release the handle so it seems to be working normally.

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[Carnivore]

Bump...

I checked DRL status with my new Techstream software and the daytime running light function is, in fact, enabled in the ECU but they still aren't coming on.

I'm most suspicious of the parking brake switch contacts since that's what foghorn narrowed it down to. But I jiggled the parking brake lever around to check for a loose connection but there was no response at all from the DRL. When I release the parking brake lever the dashboard brake light goes out normally. Does the DRL function use a different sensor/switch for the parking brake status than the one that controls the dashboard brake light?

Finally, if it doesn't come down to the parking brake switch contacts, is there a separate fuse controlling the daytime running lights? Separate from the regular headlight functions, that is? My low & high beams work normally when the lights are manually turned on.

[JuneBug]

Are you sure you HAVE daytime running lights? It was never standard equipment on the 4.3 except in Canada where it's mandatory. I have DRL's but they show up as a $40 option on the window sticker.

[Carnivore]

Originally Posted by JuneBug

Are you sure you HAVE daytime running lights? It was never standard equipment on the 4.3 except in Canada where it's mandatory. I have DRL's but they show up as a $40 option on the window sticker.

Yes it was an included option on mine and I'm quite used to seeing them working until recently.

[Rickl]

Originally Posted by Carnivore

Does the DRL function use a different sensor/switch for the parking brake status than the one that controls the dashboard brake light?

The electrical diagrams show a single sensor/switch on the parking brake which connects to ground when the parking brake is activated. This signal is then sent to the ECM which in turn controls the PB warning light, and the operation of the DRL's. So if your warning light comes on/off as you operate the PB, then I think you can assume the PB is not the source of your problems.

Originally Posted by Carnivore

is there a separate fuse controlling the daytime running lights? Separate from the regular headlight functions, that is? My low & high beams work normally when the lights are manually turned on.

There are not separate fuses. The DRL's are actually the two high beams switched into a series circuit so that each one operates on 6volts. Because this is a series circuit, the DRL's will not operate at all if either high beam is burnt out.

I would just like to have you check a few things.

• Are you absolutely sure that both of your high beams are working, and that when you turn on the high beams the light coming from the headlight isn't just the low beams remaining on. In other words do you see 2 filaments burning in each headlight housing.? The high beams are the bulbs closest to the center of the RAV.
• Are your high beams at 100% brightness?
• DRL's will not work if the regular headlights are turned on
• DRL's will not operate unless the engine is actually running
• DRL's will not work if the parking brake is on
• Summary: Turn off regular lights, release parking brake, then start car. Do you have any lights at all?

There are 4 relays which control the headlights. Depending on your answers we can probably narrow that down a little.

[Carnivore]

Rick, I think you nailed it. I double checked and one of the high beam bulbs is burned out in normal operation. I had no idea the DRL curcuit ran the bulbs in series so when one burns out they both stop working. That would totally explain it.

I'll replace the bulb at my earliest opportunity and I expect that will solve the problem.

Thanks.