Front Turn Signals Not Working

I’ve made a few threads on this topic but at the time I didn’t fully understand the issue, so I figured I’d restart. This might be kind of long so I apologize in advance.

In January, I bought a 2012 Tacoma from a dealership that had recently been traded in. I was told when I purchased the truck that the headlights had been replaced by the previous owner before it was traded in. Beyond that, they didn’t know much about it. The headlights are AlphaRex Luxx Series with sequential signals. They determined the DRL wiring harness was the issue. Since I lived 4 hours from them, they sent me a new one after I bought the truck, suggesting that this would be a quick fix.

About a week later I received the new DRL harness and I replaced it with no issues. However, this did not fix the problem. I got in contact with AlphaRex support and they told me that the issue must be that the truck needs “SR5 DRL converters” which they sent me in the mail a few days later. Even after installing those converters, nothing changed, in fact the DRLs altogether did not work with the converters, seeing as the part was for 2005-2011 Tacos, and not mine.

Fast forward about a month and I mapped all the wiring. It was kind of messy since the previous owner got “creative” with the wiring, but after checking all the pins and fuses, everything was in the right place and nothing was burnt. I finally broke down and purchased myself a multimeter and tested everything. I found that when plugged into the battery and fed the signal directly, the signals would work properly. However, when I plugged them into the truck, the signals stopped working. My local dealership of course blames the aftermarket lights and says they are the problem, even though my testing points to the issue being on the truck side.

I’m really stuck here and unsure what to do. I don’t want to spend the money to replace the lights, especially if they are not the issue. Does anyone have any insight into my problem? Any help is appreciated.

 

An obvious question.. did you multimeter test the truck side of the plug? Any visible corrosion?

 

An obvious question but something I missed haha. I just checked with my old truck and the signals are bouncing back and forth between 3 volts and 6 volts while signaling and then holding steady when the signal isn’t on. On the new one, they are only receiving around 0.23 volts at max while the signal is on. For some reason it looks like the truck isn’t sending enough power to the signals. Any ideas?

 

I’m not the best with electrical but I would look for any fuses being blown, grounding, and then follow any wires back.

 

Do you know if the truck has factory DRL/tow package? There are 2 different flasher/wiring configurations depending on what you have.

 

I have the tow package and I’ve been using that wiring diagram in my troubleshooting. There are some abbreviations I have been confused about though.

 

Do you have a test light?

What are you confused about? I'm sure I can point you in the right direction.

 

I do have a test light. I used the OEM headlights from my other truck and confirmed the signal still did not work. I’ll attach a picture of which abbreviations are most confusing. Thanks.

 

Ok what you have circled on the Turn Signal Flasher and Combination Switch are the abbreviated circuit IDs, they are just what Toyota calls the circuit.
You don't really need to worry much about what they mean, we can infer their purpose pretty easily by following the diagram.

The triangles you have circled are Ground Point's, each Ground Point has an ID that corresponds with it's location on the truck. Ground Point's starting with E are in the engine bay, B are Body/Frame, and I are Instrument Panel.

Anything else you want to know just ask.

 

If it were me, I'd start at the 1L connection.
You can test signal to and from the the flasher relay.
Which means you'll test signal from the turn signal switch and out of the flasher........

 

Well, I looked. I might have to take that back.
As the 1L is on the BACK of the interior fuse panel. And that's not "easy" to get to.
But none the less.....

 

Thank you both. I have been busy lately but am going to work on them soon and will keep you updated.

 

Following. I have a 2012 Tacoma with Alpharex headlights, turn signals don’t work but getting the “hyperflash” audible fast-click inside the cab. DRLs appear to work however. Think DRLs automatically came on the previous OEM headlights, no way to disable them sitting in the cab though.

 

Thought I would update everyone on this issue since it got extremely ridiculous to fix.

I took the truck to almost every car wiring, aftermarket parts, truck parts, etc store you can think of. None of them had any clue. Eventually I broke down and went to the local Toyota dealerships in my area. The first refused to even look at it, telling me he could see right away the aftermarket lights were the issue. I knew this wasn’t true because I had tested the power and plugged in OEM lights and I knew that the truck just wasn’t sending power to the signals.

After that incident I went to a second dealer and they agreed to look at it. They determined that it was a wire in the harness that had gone bad and wasn’t powering the signals. After I saw the dealership price of around $4500 to replace a wiring harness, I said thanks and headed out the door.

Ended up running two jumper wires myself from the signal to the lights. So far I’ve had no issues and everything else works perfectly.

Hoping anyone else who had issues in this thread got them solved!

 

Thanks for the update.
Good the hear it’s fixed.