P0708 Transmission Range Sensor Circuit High Input

P0708 indicates a high input from the transmission range sensor circuit. The control module is seeing an excessive or implausible selector signal.

Code details

Generic OBD-II · P0

System: Transmission
Code type: Generic (SAE / ISO controlled)
Standard: SAE J2012 / ISO 15031-6

Diagnostic boundary

A diagnostic trouble code reports that a monitored test failed. It does not prove one specific part is bad, and manufacturer logic can add vehicle-specific conditions.

Do not clear the code and return the vehicle without checking for a repeatable high-signal condition.

Symptoms of P0708

Harsh, delayed, or slipping shifts, or being stuck in one gear.
Check-engine light, sometimes with limp-home mode.
Flaring RPM or a shudder under load.

Common causes of P0708

Low or degraded transmission fluid.
A failing speed sensor, shift solenoid, or pressure-control circuit.
Wiring, connector, or internal hydraulic/mechanical faults.

Useful checks before replacing parts

Measure range sensor signal voltage and compare it with expected values while moving the shifter through every range.
Inspect for open grounds, short-to-voltage faults, connector spread, corrosion, and wiring damage near the transmission case.
Review whether the fault appears with movement, heat, moisture, or only after recent range sensor or linkage work.

Related OBD-II codes

These nearby transmission entries can help compare wording and pin down the fault area.