Turn Signal Electrical Help (1 Viewer)

[ianacole]

I'm leaning towards the hazard switch being the issue, but wanted to run it by those much more knowledgeable than I.

Using the schematic from the FSM (image attached), GL (Green/Light Blue) comes from the hazard switch, through the turn signal switch, then routes to either GB (Green/Black) or GY (Green/Yellow) based on the direction of the turn signal switch. This should be coming off the battery (12V), through a 15 amp fuse, then the subsequent switches. When I measure the voltage from the connector on the GL wire to ground, I get ~2V, and given that most bulbs are 12V, as is the flasher, this sounds to me that their isn't enough applied voltage to get the flasher and bulbs firing. Could the hazard switch be the cause of this drop in voltage?

The hazards work just fine.

Thoughts? Thanks!

 

[Pin_Head]

If it is the turn signals that are the problem, check for a voltage on the green/white wire at the flasher with the turn signals on. If it is substantially less than 12V, then either the hazard switch contacts are bad or the turn signal fuse is bad or the wire connections in between are bad. If it is 12V, then check the voltage on the GL wire on the other side of the flasher. If it is substantially less than 12V, the flasher is bad. If it is 12V, then check the GL wire connection at the turn switch.

Check for voltage on the same wire with the hazards turned on. Should be 12V and the lights should blink.

 

[ingomar]

I think normal flow (no 4-way flash) is thru the GW wire to the flasher, then to the turn signal switch, and on to the L or R bulbs.
When you pull the hazard switch, it by-passes the turn signal directional switch. Power flows from GW, thru flasher to GL, and then to both GY and GB and on to the L and R bulbs.
Since L and R both work in 4-way, but only one side from the directional switch, my guess is the problem lies in the turn signal directional switch or the wiring between the switch and the intersection point where the 4-way flasher circuit ties in.
And just so you know: with me, 2 wires offer a 50/50 chance; 3 or more and the odds go down! Good Luck, this stuff is a PIA!

 

[ianacole]

Thanks guys. I tested at the GW wire on the flasher. With the turn signal switch in either direction, nothing. With hazards on, 12V.

It wouldn't surprise me if it's in the wiring, or the turn signal switch, or both. When I step on the brakes, as I just discovered, the hazards stop flashing. It's a GM steering column, I've been told, so I have no idea if the turn signal switch has been spliced in correctly. Heck, I don't even know what car the column came out of to try and order a new switch

 

[ingomar]

I would think that there should be 12V at the GW wire above flasher no matter if hazard switch is pulled or not. Using an in-line fuse to protect things, you might try jumpering 12V to the GW wire to see if directional signals then work.
Not on FJ's, but I have had turn signal problems that at least once the guys at Painless wiring were able to help me with.

 

[Pin_Head]

Since L and R both work in 4-way, but only one side from the directional switch, my guess is the problem lies in the turn signal directional switch or the wiring between the switch and the intersection point where the 4-way flasher circuit ties in.

What do you mean? The turn signals will blink on only one side and the other side is dear?

If so, then the problem is likely in the turn switch or downstream of the switch.

 

[ingomar]

Well, I was thinking about a previous post I read ( maybe completely unrelated) in which I thought the poster said "one side blinks, and the other doesn't". That's why I thought the trouble might be in the directional switch or after it. After looking at the print again (and Edison Jr. I'm not) it looks like the power normally supplied to the flasher comes maybe from a key-switched source, and activating the emergency flashers pulls power from another source that might be hot all the time. So if he doesn't have power to the flasher except when the 4-ways are on, maybe the problem is in the emergency switch? Just a thought, and that's why I suggested jumping 12V to the GW wire.