I had a feeling that it was you. LOL Welcome back and boy do I wish I was in Florida. It's 20 degrees here and waiting for a bad snowstorm tomorrow. Ugh!
Regardless, when you place it in drive, does the indicator show D? I ask because I'm questioning if the transmission range sensor is bad. Here is how it works.
The transmission range sensor has six separate resistors in series. Each resistor has an output connection corresponding to a transmission position (P, R, N, D, 1, 2).
The PCM applies a 5.0-volt reference signal to the TR pin 30. The signal return circuit, pin 46, supplies a ground path to the sensor. As the transmission is shifted, the TR sensor output wiper arm moves to a corresponding resistor connection (based on gear selection). The six inline resistors provide a separate voltage drop for each transmission position. Based on the voltage signal, the PCM identifies the current transmission shift lever position.
So, I suspect that either the TR has failed, the linkage isn't fully placing the TR in the drive position, or there is an electrical issue. However, if there is an issue within the circuit, I wouldn't think it would be limited to just reverse.
If you look below, I attached the diagnostics for testing. Pic 1 indicates the use of a breakout box, which most people don't own. Since that is the most likely case, you will need to check the return signal resistance at the PCM or the sensor itself.
Pic 2 shows the resistance based on gear selection. Pics 3 and 4 provide the location and directions for removal and replacement. Pic 5 is a pinout of the PCM. I highlighted the pins involved. Pin 30 provides the 5v reference and pin 46 is the signal return pin.
Since the vehicle sits a lot, you may want to confirm there isn't a corrosion issue on the connectors as well.
I hope this helps. Stay warm and let me know if you have other questions.
See pics below.
Images (Click to enlarge)
Saturday, January 15th, 2022 AT 2:36 PM