Turn signal problem

DMHENT

MEMBER
2013 FORD F-150
5.0L
V8
4WD
AUTOMATIC
141,000 MILES

I put a new multi-function switch in because my wipers quit working properly. Now everything works properly except the turn signal. It works in lane change mode, flashes three times, but then stops. If I hold the handle it works, just not on its own. I thought it might be a bad switch so I got another one and same thing happens. Any suggestions?

Thursday, June 6th, 2019 AT 2:11 PM

2 Replies

ASEMASTER6371

MECHANIC
52,797 POSTS

Good afternoon,

The signals are controlled by the Body Control Module.

The serial data line is what controls it. You command the lights to come on and a signal is sent to the module which activates the lights according to your command.

I attached a diagram for you to view.

You will need an advanced scan tool to monitor the BCM outputs.

Roy

Images (Click to make bigger)

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Thursday, June 6th, 2019 AT 2:43 PM

BMDOUBLE

MECHANIC
1,139 POSTS

Have the part number verified with your VIN number at a Ford dealership. There are more than one type and aftermarket manufacturers sometimes get it wrong or make a “one fits all” part.

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Monday, June 24th, 2019 AT 7:23 PM