DTC P0203 Injector 3 Control Circuit. Chevrolet Monte Carlo 2000

For 1990-2009 cars only

Makes 🢒 Chevrolet 🢒 2000 🢒 Monte Carlo 🢒 DTC 🢒 DTC P0203 Injector 3 Control Circuit

Engine Controls Component Views
Engine Data Sensors-MAF, EVAP Vent, EVAP Purge, EGR
OBD II Symbol Description Notice
Handling ESD Sensitive Parts Notice

Circuit Description

The PCM controls the fuel injectors by using an ignition feed driver and ground circuit within the PCM. The driver has the ability to detect an electrical malfunction in the ignition feed or ground circuit. If an electrical malfunction occurs in the fuel injector circuit for engine cylinder #3, the ignition feed driver signals the PCM to set DTC P0203.

Conditions for Running the DTC

The engine is running.

Conditions for Setting the DTC

•	The PCM detects an electrical malfunction on the injector circuit for engine cylinder #3.

•	The condition is present for at least 30 seconds.

Action Taken When the DTC Sets

•	The PCM will illuminate the malfunction indicator lamp (MIL) during the second consecutive trip in which the diagnostic test has been run and failed.

•	The PCM will store conditions which were present when the DTC set as Freeze Frame/Failure Records data.

Conditions for Clearing the MIL/DTC

•	The PCM will turn OFF the malfunction indicator lamp (MIL) during the third consecutive trip in which the diagnostic has run and passed.

•	The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.

•	The DTC can be cleared by using a scan tool.

Diagnostic Aids

The misfire history counter may be useful in determining which injector circuit is malfunctioning. If DTC P0300 was set, look at the Misfire History display for each cylinder. The largest value stored in the misfire history counters will indicate the location of the malfunctioning injector circuit or injector.

Check for the following conditions:

•	Poor connection at the PCM or fuel injector -- Inspect harness connectors for the following conditions:

-	Backed out terminals

-	Improper mating

-	Broken locks

-	Improperly formed or damaged terminals

-	Poor terminal to wire connection

•	Damaged harness -- Inspect the wiring harness for damage.

If the DTC cannot be duplicated and is determined to be intermittent, reviewing the Failure Records can be useful in determining when the DTC was last set. Also refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

Checks for malfunctioning fuel injector control circuit or ignition feed wiring.

Checks for a malfunction in the fuel injector ignition feed circuit.

Checks for a short to ground in the injector control circuit.

Checks for an open in the fuel injector control circuit.

This vehicle is equipped with a PCM which utilizes an Electrically Erasable Programmable Read Only Memory (EEPROM). When the PCM is being replaced, the new PCM must be programmed.

DTC P0203 - Cylinder #3 Fuel Injector Control Circuit

Step

Action

Values

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

With the engine idling, monitor Specific DTC info for DTC P0203 on the scan tool.

Does the scan tool indicate DTC P0203 failed this ignition?

Go to Step 4

Go to Step 3

Turn ON the ignition, with the engine OFF.
Review and record scan tool Failure Records data.
Operate the vehicle within Failure Records conditions.
Monitor Specific DTC info for DTC P0203 on the scan tool.

Does the scan tool indicate DTC P0203 failed this ignition?

Go to Step 4

Go to Diagnostic Aids

Turn OFF the ignition.
Disconnect the PCM.
Turn ON the ignition, with the engine OFF.
Using a DMM, measure the voltage between the cylinder #3 fuel injector control circuit at the PCM connector and ground.

Does the cylinder #3 fuel injector control circuit measure near the specified value?

B+

Go to Step 5

Go to Step 9

Test the fuel injectors. Refer to Fuel Injector Solenoid Coil Test - Engine Coolant Temperature Between 10-35 Degrees C (50-95 Degrees F) or Fuel Injector Solenoid Coil Test - Engine Coolant Temperature Outside 10-35 Degrees C (50-95 Degrees F) .

Did you find a faulty injector?

Go to Step 17

Go to Step 6

Turn OFF the ignition.
Disconnect the cylinder #3 fuel injector.
Turn ON the ignition, with the engine OFF.
Measure the voltage between the cylinder #3 fuel injector control circuit at the PCM connector and ground.

Does the cylinder #3 fuel injector control circuit measure near the specified value?

0 V

Go to Step 7

Go to Step 16

Inspect for the following conditions:

•	The ignition feed circuit in the wire harness between the fuse and the cylinder #3 fuel injector for an intermittent open.

•	The cylinder #3 fuel injector control circuit between the PCM and the injector for an intermittent open or short to ground.

If a problem is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 19

Go to Step 8

Inspect for poor terminal connections at the cylinder #3 fuel injector connector.
Check the cylinder #3 fuel injector control circuit for poor terminal connections at the PCM connector.
If a problem is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 19

Go to Step 18

Turn OFF the ignition.
Disconnect the cylinder #3 fuel injector connector.
Turn ON the ignition, with the engine OFF.
Measure voltage between ignition feed circuit at the cylinder #3 fuel injector connector and ground.

Does the ignition feed circuit measure near the specified value?

B+

Go to Step 10

Go to Step 14

Probe the cylinder #3 fuel injector control circuit at the cylinder #3 fuel injector harness connector with a test lamp connected to B+.

Does the test lamp illuminate?

Go to Step 15

Go to Step 11

Turn OFF the ignition.
Install a fused jumper between the cylinder #3 fuel injector control circuit and the ignition feed circuit at the cylinder #3 fuel injector harness connector.
Turn ON the ignition, with the engine OFF.
Probe the cylinder #3 fuel injector control circuit at the PCM connector with a test lamp connected to ground.

Does the test lamp illuminate?

Go to Step 12

Go to Step 13

Inspect for poor terminal connections at the cylinder #3 fuel injector connector.
If a problem is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 19

Go to Step 17

Locate and repair open in the cylinder #3 fuel injector control circuit. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 19

Locate and repair open or short to ground in the cylinder #3 fuel injector ignition feed circuit. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 19

Locate and repair short to ground in the cylinder #3 fuel injector control circuit. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 19

Locate and repair short to voltage in the cylinder #3 fuel injector control circuit. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 19

Replace malfunctioning fuel injectors. Refer to Fuel Injector Replacement .

Did you complete the replacement?

Go to Step 19

Important:: The replacement PCM must be programmed.

Replace the PCM. Refer to Powertrain Control Module Replacement/Programming .

Did you complete the replacement?

Go to Step 19

Use a scan tool to Clear the DTCs.
Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

Go to Step 2

System OK