OBD-II code · Powertrain (generic)

P07C9 Intermediate Shaft Speed Sensor C Circuit Low

Intermediate shaft speed sensor C (third intermediate sensor in heavy-duty or hybrid-coupled transmissions) signal voltage below the lower limit.

Is it safe to drive with P07C9?

Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.

Common causes

  • Most likelySignal wire shorted to ground
  • Less likelyConnector pins corroded - high contact resistance
  • Less likelyHarness chafing through insulation

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

Repair at a glance

Difficulty
Medium
DIY friendly
Best left to a mechanic
Typical labour
0.5–2.5 h
Emissions test
Usually unaffected
Parts involved
Intermediate Shaft Speed Sensor C, Sensor Wiring

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.