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2017 Evora 400 (Manual)
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Discussion Starter · #1 ·
I took my Evora 400 out earlier this week and noticed the right hand directional indicators were not working. When I flip the stalk to the left, I get the blinking light on the dash, clicking sound, and all the lamps flash on the left side of the car. When I flip the stalk to the right, I get nothing.

in-cabin you can see no flashing or clicking when signaling right

outside of the car, same result, none of the lamps are lighting up, turning on the hazards also results in only the left lamps lighting, which rules out the stalk being a problem.

I did some digging on the forum and found this example of a similar issue on a 2010 Evora, but never a certain resolution or update. @Phontsolo - did you ever figure this out?

I studied the Evora 400 service manual extensively and found the wiring diagram below which is the equivalent for the Evora 400 that was referenced in the 2010 Evora thread with a similar issue. The integrated control module takes inputs from the stalk and hazards individually and outputs them to the left and right indicators. This diagramshows how the left (ICM pin A2) and right (ICM pin A14) lamps are wired separately and makes me suspect that A14 from my ICM is not outputting properly. I also noticed that the alarm system is wired into the lamps separately from the ICM. I tried locking and unlocking the car, which lit all of my indicators normally. I think I've ruled out a faulty stalk, dead lamps, or a larger wiring issue. I'm 90% certain that the ICM is the culprit here, but want to make sure there's not something simple I'm missing or any other ideas before I order a new ICM.

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How about your hazards? Do they work properly?
 

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I mean what you've said (lights work on lock/alarm, don't work on hazard or turn signal) would indicate something unique to the hazard turn signal circuit.

Before assuming ICM I'd try to see if there is a relay involved that isn't shared with the alarm circuit. Try cheap before expensive and all that.

(I'm struggle bussing this morning with that diagram - so apologies if it does show the output path to lights, but I'm not seeing it)
 

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Discussion Starter · #5 ·
I mean what you've said (lights work on lock/alarm, don't work on hazard or turn signal) would indicate something unique to the hazard turn signal circuit.

Before assuming ICM I'd try to see if there is a relay involved that isn't shared with the alarm circuit. Try cheap before expensive and all that.

(I'm struggle bussing this morning with that diagram - so apologies if it does show the output path to lights, but I'm not seeing it)
The diagram shows the pin A14 from the ICM "RH DI O/P" going the the RH front lamp, RH mirror, and RH Rear DI.

I can't seem to find any relays for the directional indicators. From what I'm seeing, the ICM acts in place of a traditional turn signal relay.

I already checked fuses C11, C12, C16, and C18 depicted in the diagram below.

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2011 Evora S, 2017 BRZ Yellow, 2019 Ranger Lariat FX4
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From what you describe it is the ICM. Possibly the output wire from the ICM, A14 to the M34 splice.

disconnect the ICM and apply power to the A14 wire.

If the issue is not the ICM you should get get a fast click inside to indicate a external failure.
 

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Discussion Starter · #7 ·
From what you describe it is the ICM. Possibly the output wire from the ICM, A14 to the M34 splice.

disconnect the ICM and apply power to the A14 wire.

If the issue is not the ICM you should get get a fast click inside to indicate a external failure.
I finally found a 12v power supply so I don't have to run leads from my battery. Before I hook anything up I was wondering if I apply 12v to A14 on the harness, should I utilize the ground A15 on the harness or somewhere else?

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I finally found a 12v power supply so I don't have to run leads from my battery. Before I hook anything up I was wondering if I apply 12v to A14 on the harness, should I utilize the ground A15 on the harness or somewhere else?

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I would just pick a chassis ground, But A15 would work.
 

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Discussion Starter · #9 ·
A little update... I tested at the harness right off the ICM and the right indicator lamps are working. I have an ICM on order through my local dealer and will update again once it's installed!

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ICM Arrived yesterday, installed today and right side turn signals are working again!

I made a video of the installation for anyone who runs into this issue in the future.
Thanks for the fix update and the install video! That will help others down the road.
 

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Discussion Starter · #15 ·
What an insane rabbit hole! What do you think caused it to fail in the first place?
I have no clue what caused it. It was working fine when I drove the car on Tuesday, but wasn't when I drove it on Saturday. It didn't work on the first right turn I took that Saturday, so it didn't show any signs of failure or work intermittently before failing. My car is always stored in my garage and the ICM looked perfectly fine when I took it out.
 

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2018 Evora 400 Tangerine Dream MT
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Hmm, this is the first time I've heard of this failing.

What's really impressive is the fact that you got a good camera angle in the passenger footwell while also getting your hands in there.
 
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