tranny downshift with turn signal

[alberta 7.3]

Postin' this for a buddy, 97 F250 7.3 When he's driving and turns on his signal to change lanes, the truck will downshift when the light is on (he isn't to mechanically/electrically inclined, and this is the extent of info he told me.) I told him it's probably the signal switch going on him, feeding power to the brake wire when the signal is on, giving the PCM the impression brakes are being applied. Has anyone else encountered something like this, and what would be the cause?

[J0hnny]

mmm Lots of issues related with turn signals lately...

Mines just quit working one day :S

[Chad T]

Not long ago when I would turn my signal on my RPM's would go up about 200-400 and kick my cruise control out. Turned out my brake light was bad. Doesn't hurt to check.

[jfines@cox.net]

I would say a short. When you are driving at say 45, your tranny has the torque converter locked up. And if you tap the brake, the T/C unlocks.

So I would be that the turn signal is shorted to the brake system and signaling that you touched the pedal.

Check your bulbs and sockets. then go from there.

[pitpig]

Originally Posted by Chad T

Not long ago when I would turn my signal on my RPM's would go up about 200-400 and kick my cruise control out. Turned out my brake light was bad. Doesn't hurt to check.

Mine did the same thing. Left tail light was out

[fordnut85]

Start with checking the bulbs and the sockets first, if ya don't find anything there there is a good chance it is the multi function switch

[alberta 7.3]

Talked to buddy, RH rear signal bulb was pooched. Thanks for the help