P07E8

Code

Generic P — Powertrain

Transmission Range Control A Circuit/Open

Brand: Generic

Type: P — Powertrain

Views: UK: 19 EN: 50 RU: 19

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Open or high-resistance wiring in TR (transmission range) Control A circuit
Corroded, loose or damaged connector at the transmission range sensor/switch
Failed transmission range sensor / park/neutral position switch (TRS)
Blown fuse or poor power/ground supply to the sensor circuit
Damage from chafing, rodent chewing, or flex-point break
PCM/TCM internal fault or poor PCM connector contact

Symptoms

Check Engine / transmission warning lamp illuminated
Vehicle may not start (won't crank or start unless in Park/Neutral detected)
Transmission stuck in limp/low gear or limited shift functionality
Gear selector indicator incorrect or not matching actual gear
Intermittent loss of drive or erratic shift behavior

What to check

Read freeze frame and related transmission codes with a scan tool; note gear status and conditions when code set
Visually inspect transmission harness and connectors for damage, corrosion, or water intrusion
Check fuses and power/ground circuits serving the TR sensor
Perform wiggle test on harness while monitoring the TR A signal with scan tool or multimeter
Measure continuity/resistance between sensor connector and PCM connector pins
Verify proper shift cable/lever adjustment and transmission linkage operation

Signal parameters

Typical reference voltage: ~5.0 V (may be key-on reference) — varies by manufacturer
Closed switch state: signal near 0 V (ground) or pulled to reference depending on design
Open circuit: no continuity; multimeter shows very high resistance or open (OL)
When shifting through positions the TR A signal should switch between defined states (0 V / ~5 V or open/closed) — use wiring diagram for exact expected values
Continuity from sensor ground to chassis ground should be low (

Diagnostic algorithm

Use a scan tool to confirm P07E8 and check for accompanying transmission or starter-related codes. Record freeze frame data and present gear state.
Visually inspect the TR sensor connector, harness, and nearby wiring for damage, corrosion or water. Repair visible damage before further testing.
With ignition ON (engine off), backprobe the TR A connector and verify reference voltage and signal behavior while moving the gear selector through positions. Compare to vehicle wiring diagram for expected pins and voltages.
Check continuity between the TR A terminal at the transmission connector and the corresponding PCM terminal; repair any open/high-resistance circuits.
Test sensor switch continuity: with connector disconnected, actuate the sensor/shift lever and measure continuity/resistance. Replace sensor if contacts remain open when they should be closed (or vice versa).
Check and verify power supply fuse and ground circuits for the sensor; repair poor grounds or replace blown fuses.
If wiring and sensor test good, inspect PCM connector for bent pins or corrosion. If available, swap with known-good PCM or perform bench diagnostics per manufacturer procedures before replacing PCM.
After repairs, clear codes, perform relearn procedures if required, and road test to confirm proper operation and that code does not return.

Likely causes

Broken wire or pinched harness at transmission flex section or shift linkage area
Connector corrosion/contamination at transmission sensor
Failed TR sensor (open internal contact) on the transmission
Poor ground or blown fuse feeding the sensor circuit
Incorrect shift cable/lever adjustment preventing proper switch actuation

Fault status

⚠️ Status

Transmission Range Control A Circuit/Open — Open or missing signal detected in the TR A circuit. The PCM cannot verify gear position from that circuit; check wiring, connector, sensor, power/ground, and PCM connections.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 0.5-3.0 hours

Similar codes

Your experience will help others

+100 karma for a short comment :)

Was this AI description helpful?

Your feedback helps improve AI descriptions.

👍 Like 0 👎 Dislike 0

Send to email