Engine Speed Signal - Abnormal/Signal Lost

Caterpillar Heavy Equipment Critical Engine

Model: Caterpillar C15 Engine | Code: CID 190-08

Applicable Systems
EMCP 4.2

Symptoms

Engine RPM display jumps or reads zero; loss of power during acceleration; may accompany CID 341-08.

Possible Causes

  • Crankshaft speed sensor signal loss
  • Sensor wiring intermittent at flywheel housing
  • Flywheel ring gear damaged teeth

Troubleshooting Steps

  1. Step 1: Check crankshaft position sensor at flywheel housing
    Sensor mounted securely, clean
  2. Step 2: Measure sensor resistance (500-1500 ohm typical)
    Resistance within range
  3. Step 3: Inspect flywheel ring gear for missing/broken teeth
    All teeth intact and clean
  4. Step 4: Replace sensor if resistance out of spec
    New sensor resistance nominal
  5. Step 5: Clear codes with Cat ET and road test
    No active codes, RPM stable

How to Reset

Clear with Cat ET; perform key cycle after sensor replacement.

Common Replacement Parts

  • Crankshaft Position Sensor P/N: 146-4273

Frequently Asked Questions

  • Q: Difference between CID 190 and CID 341?

    CID 190 is crankshaft speed sensor; CID 341 is camshaft position sensor. Both can cause starting issues when faulty.

Source: baijiahao.baidu.com Cat C18 sensor guide

Category: Heavy Equipment