SJB / Turn signal problem

PeterMC

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2010 S197

I was doing some voltage tests on a friends S197 while installing a sequencer in the rear RH turn signal, and I managed to short the turn signal power to ground, the clicking stopped as I did this. Now all turn signals and hazards don't work.

Don't ask how...Very embarrassing as I've been working electronics most of my life!

I've checked the S6 fuse in the SJB is good and everything else works fine.

My questions:
With the short circuit removed would a DTC code have latched preventing further operation, requiring a reset?
Why didn't the fuse (6) blow?
How can I perform a reset?
Any other thoughts?

Thanks in advance!
 

GriffX

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The US -> EU turn signal conversion lead often to blown high-side drivers on the SJB (MOSFET?). They are not difficult to change.
I would open the SJB and control them.
 

Juice

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SJB does not store lighting codes, those codes are live.
 

PeterMC

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The US -> EU turn signal conversion lead often to blown high-side drivers on the SJB (MOSFET?). They are not difficult to change.
I would open the SJB and control them.

The US -> EU turn signal conversion lead often to blown high-side drivers on the SJB (MOSFET?). They are not difficult to change.
I would open the SJB and control them.
GriffX,
Thanks, interesting, but could a short on one turn signal (RH rear) cause all 4 MOSFETs to blow? See 86GT351’s drawings below.
The sequencer conversion was done years ago and we were looking at changing back but the short was definitely during voltage testing.
 

GriffX

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GriffX,
Thanks, interesting, but could a short on one turn signal (RH rear) cause all 4 MOSFETs to blow? See 86GT351’s drawings below.
The sequencer conversion was done years ago and we were looking at changing back but the short was definitely during voltage testing.
I think the 2010 SJBs will look different inside than the previous years, so I don't know. All I wanted to say is that you can damage the electronics without blowing a fuse.
 

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