DTC P0342 Camshaft Position (CMP) Sensor Circuit Low Voltage. Isuzu S/T Isuzu

For 1990-2009 cars only

Makes 🢒 Isuzu 🢒 1999 🢒 S/T Isuzu - 4WD 🢒 DTC 🢒 DTC P0342 Camshaft Position (CMP) Sensor Circuit Low Voltage

Engine Controls Components
Cell 20: Ignition Controls
OBD II Symbol Description Notice
Powertrain Control Module Connector End Views
Handling ESD Sensitive Parts Notice

Circuit Description

The camshaft position (CMP) sensor indicates the camshaft position so the powertrain control module (PCM) can determine which cylinder is misfiring when a misfire is present. Whenever the PCM receives an intermittent signal from the CMP, then the CMP actrivity counter will increment. In order to set a DTC, the PCM must see a minimum number of resyncs within a maximum time.

Conditions for Running the DTC

The engine is running.

Conditions for Setting the DTC

The CMP active counter is not incrementing.

Action Taken When the DTC Sets

•	The malfunction indicator lamp (MIL) will illuminate after two consecutive ignition cycles in which the diagnostic runs with the malfunction present.

•	The PCM will record the operating conditions at the time that the diagnostic fails. The Freeze Frame and Failure Records buffers will store this information.

•	A history DTC stores.

Conditions for Clearing the MIL/DTC

•	The malfunction indicator lamp (MIL) will turn OFF after 3 consecutive ignition cycles in which the diagnostic runs without a fault.

•	A history DTC will clear after 40 consecutive warm up cycles without a fault.

•	Use a scan tool to clear the DTCs.

Diagnostic Aids

•	A poor connection, rubbed through wire insulation, or a wire that is broken inside the insulation may cause an intermittent problem.

•	Thoroughly check any circuitry, that is suspected as causing the intermittent complaint, proper mating, broken locks, improperly formed or damaged terminals, or physical damage to the wiring harness.

•	Whenever the PCM sees less than 15 resyncs in 256 seconds, the counter resets to 0. Anytime a poor connection is present, the cam sensor reference activity counter stops incrementing and the cam sensor resync counter starts to increment.

Test Description

The number(s) below refer(s) to the step number(s) on the Diagnostic Table.

The Powertrain OBD System Check prompts you to complete some of the basic checks and to store the freeze frame and failure records data on the scan tool if applicable. This creates an electronic copy of the data captured when the malfunction occurred. The scan tool stores this data for later reference.

This step determines if the DTC P0342 is the result of a hard malfunction or an intermittent condition.

This step determines if the voltage is available to the CMP sensor through the PCM.

This step checks for a signal from the CMP sensor. It is necessary to supply B+ to the CMP sensor ignition positive voltage terminal in order for the CMP sensor to have B+ supplied to the CMP sensor. While cranking the engine, the CMP sensor will send a varying voltage signal that can be read by the DMM as a frequency check.

Reprogram the replacement PCM and perform the crankshaft position system variation learning procedure. Refer to the latest Isuzu Technical Communication Systems (ITCS) procedures for PCM reprogramming and the Crankshaft Position System Variation Learn for the crankshaft position system variation learn procedure.

DTC P0342-Camshaft Position (CMP) Sensor Circuit Low Input

Step

Action

Value(s)

Yes

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

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

Install a scan tool.
Start the engine.
With the engine idling observe the CMP Active counter with the scan tool.

Is the CMP Active counter incrementing?

Go to Step 3

Go to Step 4

Turn ON the ignition switch leaving the engine OFF.
Review the Freeze Frame data and record the parameters.
Start the engine.
Operate the vehicle within the Freeze Frame conditions and Conditions For Setting The DTC as specified.

Is the CMP Active Counter incrementing?

Go to Step 16

Go to Step 4

Turn ON the ignition switch leaving the engine OFF.
Disconnect the Camshaft Position (CMP) sensor electrical connector.
Connect a test light to ground.
Probe the battery positive voltage terminal of the CMP electrical connector.

Did the test light illuminate?

Go to Step 5

Go to Step 6

Connect a test light to B+.
Probe the CMP electrical connector ground terminal.

Did the test light illuminate?

Go to Step 7

Go to Step 8

Check for the following conditions on the CMP battery positive voltage circuit:

•	Poor electrical connection

•	Open connection

Repair the circuit as necessary. Refer to Wiring Repairs in Wiring Systems.

Was a repair necessary?

Go to Step 16

Go to Step 15

Turn OFF the ignition switch.
Use the correct test adapters from the J 35616 and install adapters to the CMP connector terminals A and B.
Install the correct adapters to the CMP sensor terminals A and B.
Connect the fused jumper wires between each of the adapters to the correct corresponding terminals on the CMP sensor.
Remove the fuel pump fuse.
Connect a DMM to ground.
Select the Hz scale on the DMM.
Probe the CMP signal terminal C of the CMP sensor.
Crank the engine and observe the DMM.

Does the DMM display a frequency reading that is varying between the specified values?

0.5-2.6 Hz

Go to Step 9

Go to Step 14

Check for the following conditions on the CMP ground circuit:

•	Poor electrical connection

•	Open connection

Repair the circuit as necessary. Refer to Wiring Repairs in Wiring Systems.

Was a repair necessary?

Go to Step 16

Go to Step 15

Turn OFF the ignition switch.
Disconnect the PCM electrical connector C1.
Remove all the fused jumper wires and test adapters from the CMP sensor and the CMP sensor electrical connector.
Turn ON the ignition switch leaving the engine OFF.
Connect a test light to ground.
Probe the CMP sensor signal terminal at the CMP electrical connector with the test light.

Does the test light illuminate?

Go to Step 12

Go to Step 10

Connect a test light to B+.
Probe the CMP sensor signal harness connection terminal C with the test light.

Does the test light illuminate?

Go to Step 13

Go to Step 11

Check the CMP sensor signal circuit for the following conditions:

•	Open circuit

•	Poor electrical terminal connection at the CMP sensor.

Repair the circuit as necessary. Refer to Wiring Repairs in Wiring Systems.

Was a repair necessary?

Go to Step 16

Go to Step 15

Turn OFF the ignition switch.
Repair the short to B+ in the CMP signal circuit. Refer to Wiring Repairs in Wiring Systems.

Is the action complete?

Go to Step 16

Turn OFF the ignition switch.
Repair the short to ground in the CMP signal circuit. Refer to Wiring Repairs in Wiring Systems.

Is the action complete?

Go to Step 16

Turn OFF the ignition switch.
Check for a poor electrical connection at the CMP sensor electrical connector. Refer to Wiring Repairs in Wiring Systems.
If the CMP electrical connection is OK, replace the CMP sensor. Refer to Camshaft Position Sensor Replacement

Is the action complete?

Go to Step 16

Turn OFF the ignition switch.
Check for a poor electrical terminal connection at the PCM electrical connector.
If the terminal is OK, then replace the PCM. Refer to Powertrain Control Module Replacement .

Is the action complete?

Go to Step 16

Install the fuel pump fuse if still removed.
Reconnect the CMP electrical connector if the electrical connector is still disconnected.
Clear the DTCs with the scan tool.
Start the engine.
Idle the engine at the normal operating temperature.
Operate the vehicle within the conditions for running this DTC as specified in the supporting text.

Does the scan tool indicate that this diagnostic has ran and passed?

Go to Step 17

Go to Step 2

Check to see if any additional DTCs are set.

Does the scan tool display any DTCs that you have not diagnosed?

Go to applicable DTC table

System OK