Turn signal and fuse keeps popping

carntsen

carntsen

Member
Joined
Jul 18, 2022
Messages
27
Location
Barrie, ON
Hi All,
Just picked up a 2006 TJ last week. Lights were working fine when I got, but last night the turn signals quit on me.
Previous owner installed an LED light set (tails, headlights and all markers). Note sure if it was installed professional or not, but all lights worked fine for the past week

The signals and hazards are completely dead, but running lights still come on.
In the glove box, the turn signal fuse is good.
Under the hood fuse 27 (MFSW) was blown. If I change it, still no signals. If I turn on the hazards it pops again immediately

Any advice where to start?
Thanks in advance
Cam
 
Remove the screws that hold the plastic clam shells around the steering column and inspect the harness wiring for the MFS.
Remove the MFS flasher relay and inspect the terminals for signs of overheating.
IF you determine the flasher relay is bad; ensure to replace the flasher relay with one specifically for LEDs.

https://www.amazon.com/dp/B00KQUZHRA/?tag=wranglerorg-20
 
I was thinking to just buy one of the LED flashers mentioned in other posts, but not really knowledgeable in this area. Hate to waste money on a pure guess, without some guidance. Would a bad flasher cause #27 to keep blowing?
 
carntsen said:
I was thinking to just buy one of the LED flashers mentioned in other posts, but not really knowledgeable in this area. Hate to waste money on a pure guess, without some guidance. Would a bad flasher cause #27 to keep blowing?
Click to expand...

IF the relay, harness wiring or one of the LEDs are shorted that could happen.
 
I see no signed of melt or damage in the harness. I pulled the flasher it is LED but see no brand or part #. Assume cheap ?
Is replacing the flasher the next logical step, if so any recommended brand or part number?
 
carntsen said:
Just reinserting the old flasher the fuse immediately popped...
Click to expand...

The incoming power to the Flasher is shorted to ground....
When you reinsert the flasher module was the Emergency Flasher or Turn Signals selected ?
There could be a problem with the way the LEDs were wired.
I would disconnect and remove the LEDS, reinsert the flasher module with a new fuse to see IF the problem is in the wiring or LEDs.
This will allow you decide what your next step in troubleshooting.
 
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I will do just as you describe tomorrow.
Just to clarify...unwire all 6 ( 4 markers and taillights). Just leave the wires loose in the air (not touching of course). should I unhook the resistors also? One all is unwired should I still see the expected blinking on the dash if all is good?
 
YES.... disconnect them including the resistor...
IF the problem was in the LEDs; the fuse will not blow and the flasher module will probably hyper flash.
IF the problem is in the wiring; the fuse will blow again and you will need to continue troubleshooting to find where the hot lead is shorted to ground.
 
I removed 3 of 4 corners. I cant figure out how to remove the rear right. there is no access in the wheel well, as it is blocked by the fuel evap canister etc. is there a trick to this one?

With the 3 corners off and the flasher plugged in, the fuse popped as soon as I turned on the hazards.
Could it be a defective/cheap flasher relay causing the issue?
Cam
 
update... Using a ohmmeter, I can see that the White/Yellow wire has open resistance at each light location. The White/Yellow is the running lights. I assume this is my problem wire. Note though that if I turn on the running lights and use a test light, the White/Yellow wire seems to function normally.

Not clear how this is causing the signal problems as it is a separate wire.
In the wiring diagram the front and back yellow appear to be separate wires. Would this mean I have either 2 separate shorts, or is it the multi function switch?

Cam
 
Download the PDF of the FSM and look at page 8W-52-2 of the Wiring section which identifies the wiring of the MFS and Flasher Module.
IF the MFS is off not selecting any function and when you install the Flasher Module fuse #27 blows then there is a short to ground possibly in the harness that the flasher module plugs into.

https://wranglertjforum.com/attachments/2006-tj-service-manual-pdf.14047/
 
Update.... In frustration, i gave up and took it to the local mechanic. A small fortune later the short is fixed. He ended up replacing both the multifunction switch and the relay. (both with NAPA parts).

I re-installed the LED lights. They work, but I am getting the rapid blink now. I am focused on 3 possibilities:

1. The new flasher relay is a NAPA LM470. in the description it does say 'LED Compatible', Is this the right module for the job?

2. The jeep was purchased with the LED already installed. At each front signal there is a 25w load resistor. none on the rear (ohms and brand/model not marked). Are these the right size (and Qty)? and should they even be needed with an LED relay?

Sorry for the questions.. trying to learn as I go
 
This is the flasher relay you need for LEDs

https://www.extremeterrain.com/diode-dynamics-jeep-wrangler-led-turn-signal-flasher-ep27-dd4005.html?utm_content=XTLights-Other|DiodeDynamics&T5_Var4=J153298&intl=0&utm_campaign=XTW+Wrangler+Vehicle+Medium&dialogtech=ppc&utm_source=google-pla&utm_medium=shopping&T5_Var2=shopping&gclid=Cj0KCQjw54iXBhCXARIsADWpsG9Zew8ngmYjqpdnQVAdiWtoShnUM5gT-WScPacdLWySmhA-Ld_0ZHUaArN0EALw_wcB&gclsrc=aw.ds

414622?$prodpg640x480$.jpg
 
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