OPERATION
- The sensor signal is inputted to the engine-A/T-ECU (terminal No. 89) from the detonation sensor (terminal No. 1).
FUNCTION
- The detonation sensor detects the vibration of the cylinder block caused by detonation waves, and inputs a signal to the engine-A/T-ECU.
- In response to the signal, the engine-A/T-ECU provides controls to retard the ignition timing when the detonation occurs.
TROUBLE JUDGMENT
Check Conditions
- After 2 seconds have passed since the engine starting sequence was completed.
- Engine speed is 2,500 r/min or higher.
- Volumetric efficiency is 40% or more. <Vehicles except for Hong kong>
Judgment Criterion
- Change of detonation sensor output voltage (detonation sensor peak voltage in each 1/2 turn of the crankshaft) has not been 0.06 V or more in the last consecutive 200 periods.
PROBABLE CAUSE
- Failed detonation sensor
- Open/short circuit in detonation sensor circuit or loose connector contact
- Failed engine-A/T-ECU
)
Q: Is the check result normal?
YES:
Go to Step 2 
.NO: Repair.
- Disconnect connector, and measure at harness side.
- Resistance between terminal No. 2 and earth.
OK: 2 Ω
or less
Q: Is the check result normal?
YES:
Go to Step 3 .NO:
- Check and repair harness between B-103 (terminal No. 2) detonation sensor connector and body earth.
- Check earthing line for open circuit and damage.
)
Q: Is the check result normal?
YES:
Go to Step 4 .NO: Repair.
- Check output line for open/short circuit and damage.
Q: Is the check result normal?
YES:
Go to Step 5 .NO: Repair.
