I have done some research to figure out the issue before I start replacing parts. When I put the truck in park, I can’t shift out of it or start the truck. If I manually release the shift interlock solenoid, I can get it into gear and drive with no problem. My brake lights work fine even when it’s stuck in park, but the “P” doesn’t light up red. Does this point to the shift interlock solenoid being the problem?
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It could be a few things causing the issue. It might be the brake switch, the internal transmission harness, or the neutral safety switch in the transmission. There’s an override, though. If you remove the covers from the steering column, you should find an actuator that allows the gear selector to move when the brake pedal is pressed. This actuator could be faulty, but you can manually pull it to release the gear selector and shift into gear. The brake pedal signal passes through the body control module (BCM) to tell the actuator to release, so it’s also possible the BCM has failed. It’s hard to know for sure without a proper diagnosis.
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Yes this is how I currently get her to turn on.
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I have identified the park range sensor in the transmission as the cause of my identical problem.
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I think this is my problem. Since I only received the truck two weeks ago, I simply didn’t want to make a mistake just soon. This occurs as the transmission warms up, and every symptom indicates this. I’ve noticed that it starts without any issues if I let it cool.
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Yeah, I’ve had the exact same symptoms. I have put up with it for about a year since I’ve had other priorities, but I’m hoping to drop the pan and service it this month while replacing the sensor.
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Are your batteries in good condition? I have noticed strange issues with these more recent trucks’ poor batteries. It’s also possible that the transmission range selector is malfunctioning.
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Three items. I fixed one by bending the transmission’s shift lever. The cable was rubbing against the PTO on this 550, which prevented it from fully shifting into park. Other than that, you have to replace the entire valve body since either the park switch or the shifter cable is broken or misaligned. Next time disconnect cable from transmission and manually put it in park. NG-replace valve body.