Mazda 6 Quiz
Fuel and emission control systems

Knock sensor inspection

In this manual: Fuel and emission control systems
General information — 42Engine — 23Lubrication system — 10Cooling system — 9Fuel and emission control systems — 161Engine electrical system — 17Clutch — 21Manual transaxle — 10Automatic transaxle — 110Front and rear axles — 20Steering system — 15Braking system — 104Suspension — 34Body — 201Body electrical system — 287Heater and air conditioner systems — 89Technical data — 1Special tools — 1
~1min read
Note
  • Perform the following test only when directed.
Resistance Inspection

1. Turn the ignition switch to LOCK.

2. Disconnect the knock sensor connector.

3. Measure the resistance between the knock sensor terminals A and B using an ohmmeter.

  • If not as specified, replace the knock sensor.
  • If the knock sensor is okay, but PID value is out of specification, perform the Circuit Open/Short Inspection.
Specification
Approx. 4.87 megohms
Circuit Open/Short Inspection

1. Disconnect the PCM connector. (See PCM REMOVAL/INSTALLATION.)


2. Inspect the following wiring harnesses for open or short. (Continuity check)

Open circuit
  • If there is no continuity, the circuit is open. Repair or replace the harness.

- Knock sensor terminal A (harness-side) and PCM terminal 2S (harness-side)

- Knock sensor terminal B (harness-side) and PCM terminal 2P (harness-side)

Short circuit
  • If there is continuity, the circuit is shorted. Repair or replace the harness.

- Knock sensor terminal A (harness-side) and power supply

- Knock sensor terminal A (harness-side) and body GND

- Knock sensor terminal B (harness-side) and power supply

- Knock sensor terminal B (harness-side) and body GND

Test yourself

A quick Mazda 6 quiz: every answer comes with an explanation and a link to the manual page.