What it means
The transmission control module detected that reverse could not be engaged when commanded. The code alone does not identify the cause.
At a glance
- Usually lights the check-engine light
How it works
The TCM commands reverse and checks transmission speed and ratio data for the expected reverse response. P073E sets when reverse is requested but the transmission does not engage it; possible causes include the reverse shift-control circuit, fluid or hydraulic problems, and internal reverse clutch damage.
Common causes
Most likely first.
- Reverse shift solenoid or valve body fault
- Low or degraded transmission fluid
- Internal reverse clutch or mechanical fault
- Transmission control circuit fault
Symptoms
- Reverse does not engage when selected
- Transmission warning light on
How to diagnose it
- Record freeze-frame data and review the commanded range, reported range, and input and output speeds when reverse was requested.
- Check for related transmission codes that may identify a shared speed-sensor, range-sensor, or solenoid-control issue.
- Look for fluid leaks and check fluid level and condition using the manufacturer's specified procedure.
- Inspect wiring and connectors serving the transmission range and shift controls for damage, corrosion, loose pins, or fluid intrusion.
- Compare commanded shift-solenoid states with scan-tool speed data, then test the reverse-related solenoid, valve body, and internal components as specified by the manufacturer.
Common fixes
- Correct low fluid and repair any leak.
- Repair damaged wiring or connector terminals in the range or shift-control circuit.
- Replace a reverse-related shift solenoid if testing confirms it has failed.
- Repair a valve-body fault that prevents reverse hydraulic engagement.
- Repair confirmed internal reverse clutch or mechanical damage.
Can I keep driving?
Do not drive if you need reverse to manoeuvre safely, and avoid repeated attempts to force the transmission into gear. If forward gears also slip or behave unpredictably, stop driving because further operation can increase transmission damage.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.