Intermediate Shaft Speed Sensor "A" Circuit Low

What P07C5 means

The fourth-generation RAV4 (2013-2018) uses Toyota's U760E six-speed automatic transaxle, which carries two internal speed sensors: the NT sensor watching input-turbine speed and the NC sensor watching the counter gear that represents the transaxle's output speed. The ECM constantly divides one against the other to know which gear is actually engaged, so it can set shift timing and trim engine torque and line pressure for a smooth change. P07C5 is the circuit-low branch for that counter-gear sensor, which Toyota also labels the transmission revolution sensor. The ECM stores it when the sensor's input voltage falls below roughly 0.1 V for two seconds or more, using one-trip detection logic, so the light can come on after a single drive. It is closely tied to two sibling codes on the same sensor: P07C6 flags the opposite failure when the signal climbs above about 1.9 V, and P0793 flags a lost or implausible signal when the car is moving above 25 km/h (about 15.5 mph) yet counter-gear speed reads under 300 rpm. Toyota points the trouble area at the NC revolution sensor, the internal transmission wire and its harness connector, and the ECM. Because the input is a low-voltage reading, the fault usually sits in the sensor or its wiring rather than deep in the gearset.

Symptoms

• Check-engine light on, frequently accompanied by a flashing D or gear-indicator warning in the RAV4 cluster
• Transmission drops into fail-safe (limp) mode, holding a fixed gear and giving sluggish, one-speed-feeling response
• Harsh, delayed, or poorly timed shifts because the ECM has lost a reliable output-speed reference
• Higher-than-normal engine rpm at cruising speed, or a general lack of smooth gear changes
• No obvious driveability change in mild cases, with the stored code the only sign until performance degrades

Common causes

• Damaged, corroded, or loose transmission revolution (NC) sensor connector, the most common cause of a circuit-low reading
• A short-to-ground or pinched wire in the NCO/NCB signal circuit between the sensor and the ECM
• A failed counter-gear speed sensor whose output has collapsed toward zero volts
• Chafed or broken internal transmission wire (harness pass-through) where it routes to the sensor
• Contaminated sensor tip, or metallic debris in old fluid affecting the pickup, and, least often, a faulty ECM

Diagnostic approach

1. Confirm the code and read freeze-frame — Connect a scan tool (Techstream or equivalent) and record every stored and pending code before clearing. Note whether P07C5 appears alone or with P07C6 or P0793, since all three share the same NC sensor circuit. Read the freeze-frame vehicle speed and rpm so you can reproduce the drive conditions that latched the fault.
2. Inspect the revolution sensor and connector — Verify the transmission revolution (NC) sensor connector is fully seated and undamaged, and check the sensor's mounting. Look for oil-wicked, spread, or corroded pins on the connector and any signs of a chafed internal transmission wire. A poor connection here alone can pull the signal voltage low enough to set P07C5.
3. Measure sensor-circuit continuity — Disconnect the revolution sensor connector and check the harness. Continuity across the two signal lines (NCB and NCO, terminals A-4 and A-3 at the wiring-harness connector) should read below 1 ohm end to end. Each of those terminals to body ground and to all other terminals should read 10 kilohms or higher, confirming there is no short-to-ground dragging the signal down.
4. Check the harness through to the ECM — Disconnect the B78 harness connector and the B77 ECM connector and repeat the checks: NCB and NCO lines through to ECM terminals 118 (NCB) and 117 (NCO) should show below 1 ohm continuity, and each line to ground or adjacent terminals should read 10 kilohms or higher. Repair or replace any harness or connector that fails these values.
5. Replace the sensor, then recheck — If the wiring passes, replace the transmission revolution (NC) sensor, clear the codes, and drive the monitor pattern. Re-scan for P0793, P07C5, or P07C6. If the same codes still return with a known-good sensor and verified wiring, Toyota's chart directs replacing the ECM as the last step.

Make & model notes

Toyota: On the RAV4's U760E transaxle the NC (counter-gear) sensor and the NT (turbine) sensor work as a pair, so a circuit-low P07C5 should be checked alongside its siblings P07C6 (circuit high, above about 1.9 V) and P0793 (no/low signal above 25 km/h with counter-gear speed under 300 rpm). Enabling conditions are simple: battery voltage 8 V or higher, ignition on, starter off, and no active P0793. Because detection uses one-trip logic, the light can appear after a single drive.

Toyota: The same Aisin U760E and closely related U660E transverse automatics are shared across Toyota's mid-size lineup, including the Camry, Highlander, Sienna, and Avalon, so the P07C5 revolution-sensor diagnosis on the RAV4 carries over to those models. Expect the same trouble areas and the same repair order there: connector and wiring first, sensor second, ECM last.

FAQ