GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The ECM employs an internal IC in order to continuously monitor the knock control evaluation circuit. The KS module IC contains the circuitry that allows the ECM to utilize the KS signals and diagnose the KS sensors and circuitry. The KS Module is not a replaceable component. If the ECM detects a fault in the ability of the IC to sample these signals, this DTC will set.

Conditions for Running the DTC

Tested continuously

Conditions for Setting the DTC

The ECM detects a fault in the internal knock control IC.

Action Taken When the DTC Sets

The ECM illuminates the malfunction indicator lamp (MIL) and records the operating conditions in the Freeze Frame on the second consecutive drive trip that the diagnostic runs and fails.

Conditions for Clearing the MIL/DTC

    • The ECM turns OFF the MIL after three consecutive drive trips that the diagnostic runs and passes.
    • A History DTC clears after forty consecutive warm-up cycles in which no failures are reported by this diagnostic or any other emission related diagnostic.
    • The ECM battery voltage is interrupted.
    • The scan tool clears the MIL/DTC.

DTC P1602 - Knock Sensor (KS) Module Circuit

Step

Action

Value(s)

Yes

No

1

Did you perform the Powertrain On-Board Diagnostic (OBD) System check?

--

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

2

Important: This vehicle is equipped with a Theft Deterrent System which interfaces with the Engine Control Module (ECM). Program the new ECM with the frequency code of the theft deterrent module that is currently on the vehicle.

Replace the ECM. Refer to Engine Control Module Replacement/Programming .

Is the action complete?

--

Go to Step 3

--

3

  1. Clear the DTCs with the scan tool.
  2. Turn off the ignition for 15 seconds.
  3. Operate the vehicle with the conditions that are required for this vehicle to run. Refer to Conditions for Running the DTC.
  4. Check for any DTCs.

Is this DTC set?

--

Go to Step 2

Go to Step 4

4

Were there any additional DTCs noted during the Powertrain OBD System Check that have not been diagnosed?

--

Go to the applicable DTC table

The System is OK