Honda Tech Tip: Diagnosing a Faulty Knock Sensor

Honda Tech Tip: Diagnosing a Faulty Knock Sensor

If the check engine light is lit on a customer's 1998 Honda Accord EX, with trouble code P0325, it could be caused by the knock sensor, the connection, wire harness or the Engine Control Module (ECM). Replace the knock sensor and the trouble code resets.

If the check engine light is lit on a customer’s 1998 Honda Accord EX, with trouble code P0325, it could be caused by the knock sensor, the connection, wire harness or the Engine Control Module (ECM).

Replace the knock sensor and the trouble code resets.

Tests:

1. With the knock sensor unplugged and using a digital volt ohmmeter (DVOM), check for 0.02V to 0.03V reference voltage from the ECM to the knock sensor.

2. Next use a scope and look for an AC voltage signal from the knock sensor when the engine rpm is increased. It should have a very rapid AC voltage pattern of 1V positive and 1V negative. If the signal is OK, verify that signal is correct back to the ECM. If there is no harness or knock sensor problem, always verify the connection at the ECM before replacing the ECM.

Tech Tips: The knock sensor harness is a shielded wire, so also unplug the alternator and verify that there is no interference in that circuit.

For additional tech tips, visit www.identifix.com.

Technical service bulletin courtesy of IDENTIFIX.

You May Also Like

Mullen Road Tests Solid-State Polymer Battery Pack

The results met or exceeded all requirements targeted for the first drive cycles for energy usage and driving range.

Mullen Automotive began Class 1 EV cargo van road testing with an integrated solid-state polymer battery pack. Vehicle road testing began on Feb. 26 at Mullen’s Commercial Tech Center in Troy, MI.

Mullen’s latest phase of solid-state polymer battery testing began in January with the installation of the battery pack into the Class 1 EV cargo van for testing system compatibility between the vehicle and pack. Recent performance testing has included on-road drive cycles as well as Dyno testing at an EPA-certified lab located in Northville, MI, Mullen said.

TEXA Releases IDC5 CAR 76.5.0 Update

IDC5 CAR 76.5.0 is characterized by over 2600 new possible selections for the major makes on the market worldwide.

TurnOnGreen, Endliss Power Team up to Expand EV Charging

TurnOnGreen said it will leverage EPI’s expertise in administering and executing power purchase agreements with commercial clients.

Autel’s ADAS Bay Max Vehicle Lift

Learn how this lift integrates mechanical repair, four-wheel alignment, and ADAS calibration, prioritizing efficiency and space utilization in your shop.

Switch EV Trainer Provides Tailored EV Tech Training

The Switch EV Trainer includes all of the components of a modern EV drivetrain on a compact, insulated, mobile platform.

Other Posts

Tool Time Podcast: SATA USA

In this all new episode of the Tool Time Podcast, Nadine and Eric sit down with Chris Springer of SATA USA.

Elywhere Launches in North America

Elywhere chargers can be configured to support power in the 1 MW range, providing solutions for electric fleets.

#3 Screwdriver “Tips”

What appears as one of the most basic tools in your box is far from it.

#2 Calipers & Micrometers

Calipers and Micrometers are essential measuring tools when exact precision is required.