Turn signal affecting engine

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Sep 25, 2012 | 03:05 PM

Shake-N-Bake

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From: Mesa AZ

Turn signal affecting engine

Having an odd problem with one of our F-550 6.0 liter trucks so I figure I'd ask the question just to see if anyone has experienced this before. (I tried searching and came up with zero threads...)

Driver reports the engine died when activating the left turn signal. Vehicle restarted and he made it back to our shop (luckily he was fairly close). I scanned for codes and a bunch came up but who knows how old any of them might be. Cleared the codes and the only one that returned was B1352 Ignition Key in circuit fault...however that code is quite common when these trucks are set up with PTO equipment.

So, while attempting to duplicate the problem we were unsuccessful in getting the engine to die. However, we did observe the left turn signal flashing very quickly yet all bulbs were lighting (no burnt out bulbs). Then all by itself (after 30 seconds or so) it started flashing normally. Pull back in the multi function stalk (to activate high beams) causes the turn signal to flash quickly again AND causes the idle speed to increase about 200 rpm.

At this point I am suspecting some sort of issue with the multi function switch however I can't quite understand how that can have anything to do with the engine idle speed or how that can cause the engine to stall.

Has anyone experienced anything like this before?

Sep 25, 2012 | 06:36 PM

Shake-N-Bake

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From: Mesa AZ

Update:
So, we replaced the mult-function switch and some black powder came out when we shook it about. The turn signals function much better with the new switch but we still were able to get the engine to die by pulling back on the stalk (momentary high beam). Very intermittent though....sometimes it dies, sometimes not.

Our problem is somewhere else. We are going to trouble shoot the ignition key circuit next....

Sep 25, 2012 | 07:57 PM

Yahiko

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From: Spanaway

I would look down the harness for more wire problems. I
think you will find some chafing or a pinched wire.

Sean

Sep 25, 2012 | 10:26 PM

Shake-N-Bake

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From: Mesa AZ

Quote:

Originally Posted by Yahiko

I would look down the harness for more wire problems. I
think you will find some chafing or a pinched wire.

Sean

Thanks. We are heading that direction next. Turns out that B1352 is for that little microswitch in the key cylinder receptacle that operates the chime whenever the key is left in the ignition. It would chime even with the key removed and door open. Tilting the column would make it chime louder or stop completely. We decided to disable that thing because the chime was driving us crazy. The sister truck has the same issue (chime goes off when door is open even with key out of ignition) . It was that way before the engine blew up so we know the repair shop didn't forget to hook something up when the new engine was installed...

Anyway, tomorrow we will look at the wiring some more. These trucks have some aftermarket PTO controls and the buckets have remote engine start/stop capabilities. Those controls are supposed to be disabled when PTO is not in use but something could have gone wrong with the wiring so we are going to verify those systems next.