Turn Signal Trouble

[Nick Badame Refrig/ACC]

Hi Guy's,

Today, I was doing a check over on systems before launch tomorrow for a day trip to the moon and back.. lol

And I discovered that my turn signals were acting up. At first they didn't work at all, then the worked, then not???

I did notice that when they didn't work, my 4 way flashers that operate from a switch on the dash wouldn't work either.?? Hummm

The lever for the turn signals seems kinda loose but I still hear the contacts clicking when cycled.   Now, they won't work at all.

Any ideas as to where to start looking?    89' 102C3

Thanks
Nick-

[lyndon]

My first thought is a short, since it affects both turn and 4-ways, and it's intermittent (A breaker cycling, perhaps). I'd look first for a hot breaker to verify that theory.

Don

[maria-n-skip]

Nick,

On mine MCI 8 (no standard anything) the single flasher runs both the turn and the 4 ways. It has
a flaky wire and will do the same as what you are describing.

FWIW

Skip

[lyndon]

Skip, I just peeked at my manual (MC9), and you are correct. The hazard switch is ganged (3-way) to activate both turn signals at the same time, plus the dash indicator, using the common flasher unit. So they certainly have a lot more in common in common than I thought. (I should have, as they say, RTFM.)

Of course, a hot breaker still could point to an intermittent caused by a short. If it's a flaky wire, it would not cycle in any consistent way. From what Nick said in the original post, it may have quit for good, so he should consider your theory first.

Don

[Nick Badame Refrig/ACC]

Don & Skip,

Thank You Both...

I will try the flasher first in the am..

Don, Welcome to the board..

Nick-

[lyndon]

Thanks for havin' me, Nick! I hope your solution is as simple to solve as changing the flasher.

Don

[4106-123]

push the turn signal lever right or left and leave iton  then go see if the front or rear bulbs are lit on the side you left the lever on. if only one is lit it wont allow the flasher to work right as it has to sense the load of both bulbs  to flash . at least thats how mine works in my gmc

[gus]

Nick,

The only thing they all have in common is the flasher, the signal switch and ground.

Start with these.

If it were a bulb it would only affect the signals on that one side.

Check if the brake lights work. The brake and turn signals use the same bulb filaments in the rear.

If the brake lights don't work there is a problem in the rear wiring or signal switch. The signal switch turns off the brake lights on one side when signals are flashing.

[RJ]

Check if the brake lights work. The brake and turn signals use the same bulb filaments in the rear.

Gus -

Nick has an MCI, which uses separate lights for turn signals, not integrated into the brake light circuit like your 4104.  Buffalo GMs also use separate circuits for turn & brake wiring.

Otherwise, good information!


Nick -

Not sure on the C series, but on the 7s, 8s and 9s, the turn signal flasher is up high on the post in front of the electrical panel to the left of where your foot would be if you were getting ready to step on a clutch.  IIRC, it's a Wagner HD unit, but I don't have a part number for you.  (Back in my charter days, I used to carry a spare. . .)

Once you find the flasher, make sure that the clip it snaps into hasn't come loose on the post - it's what grounded the flasher on the older MCIs.

FWIW & HTH. . .

[TomCat]

Hey Nick,

My coach showed the same symptoms, and a new flasher cured it.

Jay
87 SaftLiner

[Gary '79 5C]

Nick,

Check the alternator voltage output, Mine threw its belts ( not that you have belts ) and the turn signals were the first thing I saw go bye bye.

I now guard the volt meter one in ten times I check the temp guage.

Good Luck & if you need a hand call.

Gary Pasternak
609 703 - 8989

[gus]

Russ,

I should know better than to stick my nose into these MCI posts!!


I'll store that info away in my MCI brain file.

[Nick Badame Refrig/ACC]

Hi Guy's,

It seems to be the turn signal switch assy. After playing with it some, it started to work again and then the same thing happened.

All other systems are working fine, charging, and flasher..

Thanks for all the input. I will order a new one on monday.

Nick-