PMS medication required
The OD light on my friends truck is always lit and it won't toggle on or off. The transmission shifts fine but will never go into OD. He took it to a tranny shop and they checked the wiring from the column to the ECM and the ECM is receiving a signal when the button is toggled. The tranny is not setting any codes. He is pretty sure that the TQ is engaging. Any ideas? Could this be an ECM problem?