Intermittent turn signal

So here's a weird one. The other day my turn indicator starts hyper-flashing. Okay, no problem, I must have a dead bulb, just need to figure out which one. Turns out to be the driver-side mirror signal. Fine, so I order a replacement. While waiting for the replacement to show up, the indicator stops hyper-flashing and it looks like the signal is working again. Great, waste of money on the replacement.

Well, since I bought the Morimoto sequential turn signals, I decided to put them in any way. Guess what, the driver-side signal is not working again, but no indicator hyper-flash. Long story short, it works intermittently.

Long shot, but any thoughts? I messed with the wires in the mirror, thinking maybe a loose connection, but no. All the other signals work, so it can't be a fuse. What about the flasher relay? Could that somehow be faulty? Oh, and the mirror directional motor works fine, no issue there.

 

When the turn signal doesn't work.
Can you get it to work by turning on the flashers?

 

I'll try that next time it stops working. Of course, now that I'm asking for help, it fears being fixed and works when i don't want it to.

 

The signal did not work when turning on the flashers.

And now the plot thickens. Took a trip this morning and the TRAC OFF and ENGINE lights are on.

 

Is it just the driver side mirror signal that stops working?
Or all the driver side signals? (Headlight, mirror, and tail light)

Asking so I know where to guide you on checking.....
I got diagrams, just need to where to start. Now what light(s) don't work will help with where to check first.

 

Thanks, man. It is only the driver-side mirror. Every other signal works as intended.

 

Do you have the stock parts to put back in for testing?

 

Ok. Let me drop this here.
Just for reference.

Ideally, I like to check for power and ground at the bulb plug.
But that can be easier said, than done.

Since the other flashers on the driver side work, we can rule out the flasher relay.

Let me find the nearest connector(s) that is easiest to get to, we can check there.

The Left hand mirror goes through 1x junction connector (1C) and 2x regular connectors (IA3 and IC7)
The Ground IC7 and J4.

Let me figure out were those connectors are and get back with you.

 

Yes

 

Ok it took me a minute.
But I finally found a copy of the connector locations.

That said, most of the time, it's the wire harness between the door and the cab.
Every time you open and close the door, those wires bend. Eventually, they can just break over time.
And depending on the time, they can move just enough at the break to make contact again....Then next the door opens/closes the break contact.

Unless you wan to go straight to the bulb connector, IC7 is the easiest place to check.
It's behind the driver side kick panel.
You are looking for Pin 1 (Pink) - Power
And Pin 4 (White/Black) - Ground.

I'd use a test light, as it can act as a blinker, and you wont have to try and watch the meter bounce between 0/12v. (power side)

 

Okay. Will give that a check and report back.

 

I wish I had a picture but one of my turn signal sockets had a pin that was depressed more than the others causing an intermittent turn signal. this was with tyc bulb sockets. Had the same issue you are describing.

 

...I mean the flashers are only supposed to work half the time anyway, right?

(sorry, someone had to say it. lol. Good luck with it.)

 

ÿes and no

 

Thanks @TnShooter for those diagrams. What a PITA to get into that wiring. After checks came out good at the connector, I decided to pull the door card and start tracing the wires. First thing I noticed was a loose connector. Not sure how that happened, but it seems to be the culprit. Gonna throw a piece of electrical tape on there for good measure.

 

Kind of related issue: posted as a heads up: 2014 Tacoma. One of my front signals with the day-time running/parking lights started hyper-flashing intermittantly. Got a new bulb and replaced it and it did same thing. hmmmm.... Turns out these wedge bulbs have kind of a 2-stage installation snapping them in. (Not a simple push-in base) When they first go in, they make just enough initial contact to work...and off you go: Maybe/kind of: but they can hyper-flash because they aren't fully tight. Sometimes it takes a while. A harder push gives a slight "click" and it locks in. Much harder to remove it. The intermittent bulb I removed that was giving me the problem came out easily. I'm pretty certain this caused the initial hyper-flashing. I swapped both bulbs and kept the old ones for spares.

Issue solved