M1009 (Also) Turn signal issues

[Russm]

Noticed there is another topic describing almost the same problem as me, but in case its not the same cause, here we go:

Signalling Right flashes front and rear right signals. Braking does not affect the flashing.
Signalling Left flashes left signal on front but both signals on rear. Additionally pressing the brake causes front left and both rear signals to burn steady.
Switching on the hazard flashers is normal until brake is pressed, with brake pressed all 4 corners burn steady.

I've cleaned all grounds attached to headlights, front and rear lights. Cleaned the main ground under the dash on the driver side wall. All contacts on all bulb sockets have been cleaned. No lights are burned out.
The wiring harness going to the rear lights appears intact, with no visible wear or corrosion.

Other topic says the turn signal switch on steering column may need to be replaced.
Does anyone have anything else to try?

Thank you

 

[Tinstar]

Have you tried a different flasher to see if any difference?

 

[Bighorn]

Have you tried a different flasher to see if any difference?

This was my issue.
Everything checked out but had random flashers, stopped flashing with brake depressed etc.
Replaced BOTH the flasher relay and hazard relay.
Problem went away.

 

[Russm]

Thanks I'll try switching out those 2.


Sent from my iPhone using Tapatalk

 

[Russm]

Thanks I'll try switching out those 2.


Sent from my iPhone using Tapatalk

Switched both flashers for new ones.
Issue still exists without changes.

At least I can hear the turn signal click with the engine running now.


Sent from my iPhone using Tapatalk

 

[DREDnot]

Do you still have the blackout light control switches installed and plugged in?

Mine were removed and the main power wire(OR-OR/BLK) was jumped in the remaining connector. I took me weeks of futzing with bulbs, sockets, cleaning grounds, etc to come to the realization that the PO failed to install a jumper for the brake wires(WT-WT/BLK) in that connector. He had cut the WT/BLK wire at the brake switch and run a jumper wire all the way back to the GRN wire of the trailer harness. Symptoms were everything worked correctly...marker lights, turns, brakes, reverse, hazards...but when you had the right turn signal flashing, hitting the brakes made it steady bright right front and rear, and the left brake light would not illuminate.







I reconnected the WT/BLK wire at the brake switch, removed the long jumper wire, and made a small jumper for the blackout switch connector that went from the WT to the WT/BLK. Boom...everything works...correctly.

 

[Russm]

Do you still have the blackout light control switches installed and plugged in?

Mine were removed and the main power wire(OR-OR/BLK) was jumped in the remaining connector. I took me weeks of futzing with bulbs, sockets, cleaning grounds, etc to come to the realization that the PO failed to install a jumper for the brake wires(WT-WT/BLK) in that connector. He had cut the WT/BLK wire at the brake switch and run a jumper wire all the way back to the GRN wire of the trailer harness. Symptoms were everything worked correctly...marker lights, turns, brakes, reverse, hazards...but when you had the right turn signal flashing, hitting the brakes made it steady bright right front and rear, and the left brake light would not illuminate.

View attachment 703457

View attachment 703458

View attachment 703459

I reconnected the WT/BLK wire at the brake switch, removed the long jumper wire, and made a small jumper for the blackout switch connector that went from the WT to the WT/BLK. Boom...everything works...correctly.

Thanks for the detailed post.

I see now I forgot to mention... up until a few months ago everything worked correctly.
Then I played around in some mud.
Now I have this issue

Have beat myself up looking for some kind of damage/corrosion on the underside, coming up empty so far.


Sent from my iPhone using Tapatalk

 

[Bighorn]

Switched both flashers for new ones.
Issue still exists without changes.

At least I can hear the turn signal click with the engine running now.


Sent from my iPhone using Tapatalk

Now you have eliminated the flasher pots.
Still sounds like a grounding issue.
Anyway you can run a redundant ground wire from the battery directly to the socket in question?
Maybe just along side the truck even, just to absolutely rule out a ground issue.
There may be dirt in the trailer harness connections under the rear bumper too.

 

[Tinstar]

Mud = water.

I would literally take apart every single connector you can and inspect, clean and apply electrical grease. Including grounds.
It’s a total PITA, but necessary since the problem will not fix itself.
It will get worse most likely since corrosion from moisture will take over more and more.

Its amazing on these trucks how many gremlins disappear when you properly refresh the grounds.

 

[Russm]

I am finally able to work on my truck outside and not in a garage where I had to hide from management because car repair = bad at my last place.
I believe i have found my issue. The rear brake/turn signal wires leading into the fuse box from the engine bay appear to be caked with mud and corroded, and are probably shorting with each other. I have the picture on my phone let me get it here.

It appears that the wire bundle leading from the rear lights forms a plug held in place by some kind of big plastic c-clip. Would I be able to pop this off without breaking anything or do I need to disassemble the whole fuse box from the passenger compartment? (I can't tell from the 34p TM)

 

[Russm]

disregard this post. got pictures working on computer

 

[Russm]

Ok officially out of ideas again.

Disconnected rear lights via the plug shown earlier.
Signaling left I can hear the flasher clicking but pressing the brake makes it stop (same issue as before)

Signaling right works normally independent of brake.

So my problem is somewhere between steering wheel and fuse box.

The main ground on the left side of firewall has been thoroughly cleaned.

Anyone with suggestions?


Sent from my iPhone using Tapatalk

 

[Mg84648]

Looking at the print, it looks like everything goes through your Directional Signal/Hazard Flasher switch in the column. Its part number 1997983 in the -20P which crosses to a autozone part number SW324 for $27.
It might be the last thing to check if you isolated it from the fwd and aft lights.

 

[48cj2a]

There should be a bolt in the center of the bundle where it plugs into the bulkhead connector.

You can unbolt it and in the bundle will be three individual connectors slid into that C piece you described that holds them all together forming a single connector.

Take them apart and you can clean as needed, slide them back in and replace the bolt causing them to reseat into the bulkhead connector.

Large connector is the engine harness, two smaller connector are the front headlight and rear tail light harnesses.

 

[edpdx]

Have you replaced any of the turn lamp sockets before all of this started?

 

[Russm]

Wowwww problem fixed. Finally

The turn signal switch in the steering column was the culprit. It was covered with little brass shavings that were probably shorting out lots of things.

New switch problem fixed.

As a side note I am missing the spring and retaining ring for the lock plate that you need a compression tool to remove. Mine just slid out.
Do I need to get one of these? Seemed to work fine without it



Sent from my iPhone using Tapatalk