My 2007 trailblazer's turn signal inside is blinking fast, outside the bulb is not flashing at all. Bulb and fuse are good. What else do I need to look at to fix this? Thanks so much!

 

Have you tested for power at the bulb? Which bulb is the one that is not working properly.

 

Thanks! There is no power to the bulb and it is the right rear turn signal.

 

If the front turn signal works and the rear doesn't, the next step after checking for power at the bulb would be to check for power at the connector to the circuit board on back of the tail lamp housing itself. It'll be the dark blue wire.

Other than that, it's down to a wiring problem as the RT FUSE in the rear fuse box powers both front and rear turn signal bulbs.

 

The bulb may look good but probably isnt.

Otherwise some of the 360's had problems with the circuit boards, but are easy to replace.