P07C9

Code

Generic P — Powertrain

Intermediate Shaft Speed Sensor C Circuit Low

Brand: Generic

Type: P — Powertrain

Views: UK: 27 EN: 25 RU: 27

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Page language: EN

Causes

Short to ground in the sensor C signal wire or harness
Open or high resistance in the sensor supply/reference circuit
Failed Intermediate Shaft Speed Sensor (sensor C)
Corroded, bent, or poorly seated connector pins
Water intrusion or damaged wiring insulation
Faulty powertrain control module (rare)

Symptoms

Malfunction Indicator Lamp (MIL) illuminated
Erratic or harsh shifting (transmission may enter limp/limited mode)
Reduced performance or hesitation under load
Diagnostic trouble codes related to other speed/shaft sensors
Inconsistent or missing speed/shaft signal when monitored with a scan tool

What to check

Retrieve freeze-frame and live data with a scan tool; confirm P07C9 is current and not historic
Check for additional related DTCs (other shaft/speed sensor codes)
Visually inspect sensor C connector and harness for damage, corrosion, or pins pushed out
Wiggle test wiring while monitoring live sensor data to reproduce the fault
Back-probe the sensor connector and measure reference voltage, signal, and ground
Measure resistance/continuity between the sensor connector and PCM connector for signal, reference and ground

Signal parameters

Hall-effect/active sensor: 0–5 V square-wave (switching between ~0 V and the reference voltage) with a stable reference (typically 5 V) and low impedance ground
Variable reluctance (VR) sensor: AC voltage that increases with shaft speed (typical low-speed readings 0.1–2.0 Vp-p), no DC reference required
Typical sensor resistance: varies by application — consult OEM spec; out-of-spec resistance or open/short indicates a defective sensor
Expected behavior: present switching/AC signal that changes with intermediate shaft rotation; 'low' means signal amplitude is below expected threshold or stuck near 0 V

Diagnostic algorithm

Connect a scan tool, confirm P07C9 and note freeze-frame/live data. Check for related codes.
Visually inspect the sensor C connector, harness, and nearby components for damage, chafing, corrosion, or fluid intrusion.
With ignition on, back-probe the connector: verify sensor reference voltage (if applicable), ground continuity, and signal voltage while cranking/rotating the shaft.
Perform a wiggle test on wiring while monitoring signal for intermittent shorts or opens.
Measure resistance of the sensor (if service info provides values). Compare to OEM specs. If open or shorted, replace sensor.
Check continuity from sensor signal pin to the PCM pin. Repair any short to ground or opens in the harness. Repair or replace damaged connector pins.
If signal type is VR, use an oscilloscope to confirm AC waveform amplitude and shape while rotating the shaft. If hall-type, confirm clean square wave.
If wiring and sensor test good, verify PCM reference and ground circuits. Substitute a known-good sensor or inspect/replace PCM if all else fails.
After repair, clear codes, perform functional test/road test and verify the code does not return.

Likely causes

Damaged/shorted signal wire near the sensor or harness
Corroded or loose sensor connector
Failed sensor (internal short or loss of output)
Poor ground or reference voltage to the sensor

Fault status

⚠️ Status

Intermediate Shaft Speed Sensor C Circuit Low — the control module detects the sensor C signal is lower than expected (possible short to ground or failed sensor).

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 0.5-2.0 hours