Right Rear turn signal - not the bulb

2003 4runner SR5 V8. The right rear amber turn signal went out recently with the characteristic rapid blinking. Hazard lights work on the other three bulbs. Brake lights, reversing lights and rear lights all OK on both sides.

I looked for the obvious problem and examined the bulb and it was not blown. I tried the turn signal socket and bulb and it worked on the (other) left side, I also tried swapping the main feed socket to the rear assembly, rear light and brake light on the non functioning side and the turn signal still did not work. So I think I have eliminated the turn signal socket and the brake and rear light socket.

I did read that the rear assembly sometimes has a poor connection via the main feed so I checked all the connections on the sockets and the rear light assembly. Nothing obvious and all contacts were clean and the continuity checked out.

So before I delve into the flasher unit or fuses I thought it wise to ask this forum for any suggestions.

As with may of these apparently simple problems the solution is elusive and I hope someone has experienced a similar situation and can help me out. Many Thanks for any suggestions
Brian

 

If it ain't the bulb, then it's the fuse. I'd bet the ranch on it.

 

This happens on our aging vehicles...pop open the bulb access compartment and press the contacts that the wires go into the taillight housing itself. Press those buggers in and walla, you're blinkers will be blinking correctly again! I just did this after replacing all of the bulbs...I accidently pressed on the wire harness contacts in the back of the light housing and all was working and has been working well...

 

Thank you for the suggestions. I tried changing the fuse but that did not make any difference so I moved on to a new flasher module behind the fuse panel under the steering column. Once again no change. Following your suggestion about the contacts on the back of the rear light housing, I checked all the continuity and it seemed OK but it is difficult to see the contact from the centre bulb (Brake and tail light) through the connector to the wire harness. I did swap the connector to the other side and it worked fine. So my my next avenue to explore is replacing the tail light housing. I certainly agree that it is a very fragile system and unlike most of the durable Toyota connectors. Once again Thank You and i will post again and let you know the outcome.

 

The saga continues! I bought a new rear light assembly and unfortunately it hasn't made any difference. The new assembly works fine with all bulbs functional on the left side so I think I have eliminated the new assembly and I also swapped the connectors that connect from the harness to the rear light assembly and the problem persists on the right side.
Looking at the wiring diagram I think I am left with the possibility of a break somewhere in the harness between the connector at the right rear turn signal light and the right junction block. another possibility is the ground connection. Ive added the circuit diagram.

 

Well, think of the positive...you saved at least $150‐$200 in a ship telling you this...right?

 

@bribri53 - unless I've missed it, I haven't seen anything about investigating the other end of the signal path - the stalk on the steering column. I don't know how to check that but it fits your symptoms and it seems conceivable that some kind of failure could leave it working for one side and not the other.

 

Well the saga of the right turn signal has finally been resolved. With the help of a wiring diagram and a continuity tester I found a break somewhere on the right side of the cable harness below the light assembly. As soon as I started to take the right side panelling off I knew I was onto something. There was a huge pile of noise insulation and - You guessed it - Mice. I found the break in the turn signal cable in the harness just before the light assembly. I have had mice problems before under the dash. I spliced in a short cable and it worked.
So I guess the moral to the story is look for the simple explanation first. Good luck to anyone who has a similar problem and thanks for all the posts. I would recommend a simple 12 Volt continuity tester rather than a voltmeter which did not respond fast enough to the flashing. Thanks

 

Nice!! I'm glad it was repairable!

 

Those rat bastards.

Sorry, couldn’t pass that one up.

 

One slot to consider armoring from rodents is under the wiper cowl...that's the fresh air intake...they're gaping voids and I used some gutter guard from Home Depot and silicone to seal them up like Alcatraz...I've been rodent free since doing this 5 years ago...a good weekend job...

 

I did this after tracking down a rattle in the dash and finding an acorn atop the HVAC fan.