What it means
Intermediate shaft speed sensor C signal voltage above the upper limit. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
At a glance
- Usually lights the check-engine light
How it works
Intermediate shaft speed sensor C reports the speed of a third intermediate shaft or sensing point, where fitted in some heavy-duty or hybrid-coupled transmissions. The transmission control module sets P07CA when sensor C's signal voltage exceeds its expected upper limit, which can happen if its signal wire is shorted to reference voltage or another powered circuit.
Common causes
Most likely first.
- Signal wire shorted to reference voltage
- Connector pins corroded - high contact resistance
- Supply wire pinched against B+ source
Symptoms
- Check engine or transmission warning light on
- Harsh, delayed, or missing shifts
- Possible limp mode (locked in one gear)
- Slipping or shuddering during gear changes
How to diagnose it
- Record freeze-frame data and check live data specifically for intermediate shaft speed sensor C to see whether its reading is implausible or fixed high when the fault occurs.
- Locate sensor C using vehicle service information, then inspect its connector and harness for moisture, corrosion, pushed-back pins, or wiring pinched against a reference or battery-voltage source.
- With the fault present, gently move the harness near sensor C while watching its live reading to locate an intermittent high signal.
- Use the vehicle wiring diagram to check whether sensor C's signal wire is shorted to its reference or another powered wire.
- If wiring and connections are sound, test sensor C and its supply and ground circuits against the manufacturer's specification.
Common fixes
- Repair a pinched or chafed wire that is feeding voltage into sensor C's signal circuit.
- Clean and secure corroded or loose sensor C connector terminals, and repair damaged seals.
- Repair a damaged connector pin or restore proper terminal contact.
- Replace intermediate shaft speed sensor C if it fails testing.
Can I keep driving?
If the vehicle shifts normally and only the warning light is on, drive cautiously and arrange diagnosis soon. Avoid towing and hard acceleration; incorrect shaft-speed data can cause harsh shifts, slipping, or a protective shift mode.
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.