DTC P0202 Injector 2 Control Circuit. Cadillac Concours 1997

For 1990-2009 cars
Engine Controls Components
Fuel Injectors
OBD II Symbol Description Notice
ESD Notice

### Circuit Description

This PCM contains a General F.E.T. (Field Effect Transistor) Driver (GFD) that controls the eight fuel injector drivers. The GFD contains circuitry that is used to determine if there is a problem with any of the fuel injector circuits. The GFD has a fault line for each injector. The fault line goes high when an open, short to ground, or short to voltage is noticed in an injector circuit. DTC P0202 is set when the fault line for injector #2 is high.

### Conditions for Setting the DTC

#### Test Conditions

• | DTCs P0560 and P1376 not set.

• | Ignition voltage between 10 and 16 volts.

#### Failure Condition

An injector circuit fault is detected for 0.5 second.

### Action Taken When the DTC Sets

• | The faulty injector is disabled for the engine run cycle.

• | PCM disables Closed Loop operation.

• | The PCM will illuminate the malfunction indicator lamp (MIL) when the diagnostic runs and fails.

• | The PCM will record operating conditions at the time the diagnostic fails. This information will be stored in the Freeze Frame and Failure Records.

### Conditions for Clearing the MIL/DTC

• | The PCM will turn the MIL OFF after three consecutive drive trips that the diagnostic runs and does not fail.

• | A Last Test Failed (current) DTC will clear when the diagnostic runs and does not fail.

• | A History DTC will clear after forty consecutive warm-up cycles with no failures of any emission related diagnostic test.

• | Use a scan tool to clear DTCs.

• | Interrupting PCM battery voltage may or may not clear DTCs. This practice is not recommended. Refer to Clearing Diagnostic Trouble Codes in PCM Description and Operation.

### Test Description

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

1. If DTCs P0203, P0205 and P0208 are also set, power must be disabled to injectors 2, 3, 5 and 8.

2. Checking for short to ground in the injector 2, 3, 5, 8 Ignition feed circuit between fuse and fuel rail connector.

3. Checking for short to ground in the injector 2, 3, 5, 8 Ignition feed circuit between fuel rail connector and one of the injectors.

4. Looking for open in the injector 2, 3, 5, 8 Ignition feed circuit between fuse and splice. Also, splice may be faulty.

5. If DTC P0202 is not current, drive vehicle until DTC resets. This will bring the injectors to the temperature at which the DTC set.

6. Checking to see if injector #2 is receiving voltage. If not, the fault must be in the injector 2, 3, 5, 8 Ignition feed circuit between the splice and injector #2.

7. Checking for a shorted injector. Resistance should be between 8 to 25 ohms.

8. Checking for poor terminal contact at PCM connector C2 terminal 10.

9. Checking for an open or short to ground in the injector 2 control circuit between PCM and connector fuel rail connector.

10. Checking for a short to ground in the injector 2 control circuit between fuel rail connector and injector #2.

11. Checking for an open fuel injector. Resistance should be between 8 to 25 ohms.

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Was the Powertrain On-Board Diagnostic (OBD) System Check performed? | -- | Go to Step 2 | Go to A Powertrain On Board Diagnostic (OBD) System Check
2 | Connect a scan tool. Are DTCs P0203, P0205 and P0208 also set? | -- | Go to Step 3 | Go to Step 7
3 | Turn the key to OFF, remove and inspect the injector fuse. Is fuse blown? | -- | Go to Step 4 | Go to Step 6

4

1. Disconnect the fuel rail connector.
2. Using DMM J 39200 measure resistance to ground at fuel rail connector terminal P (engine harness side).

Is resistance more than the value specified?

5 ohms

Go to Step 5

Go to Step 17

5

1. Disconnect fuel injector #2 connector.
2. Measure resistance to ground at injector #2 connector (harness side) terminal A.
3. Repeat for injectors 3, 5 and 8.

Do any circuits measure less than the value specified?

5 ohms

Go to Step 18

Go to Step 19

6

1. Disconnect the fuel rail connector.
2. Replace the injector fuse.
3. Key ON, measure voltage to ground at fuel rail connector (engine harness side) terminal P.

Is voltage the same or higher than the value specified?

10 volts

Go to Step 20

Go to Step 21

7 | On the scan tool select Last Tst. Fail. Has this DTC failed its last test? | -- | Go to Step 9 | Go to Step 8
8 | Clear DTCs, operate vehicle until DTC P0202 resets. Does DTC P0202 reset? | -- | Go to Step 9 | Fault not present

9

1. Turn the key to OFF, disconnect fuel injector #2 connector.
2. Key ON, measure voltage to ground at injector #2 connector (harness side) terminal A.

Is voltage the same or higher than the value specified?

10 volts

Go to Step 10

Go to Step 22

10

1. Reconnect fuel injector #2 connector.
2. Record the fluid life indexes, turn the key to OFF and wait 30 seconds.
3. Disconnect PCM connector C2.
4. Key ON, measure voltage to ground at PCM connector C2 terminal 10 (harness side).

Is voltage more than the value specified?

10 volts

Go to Step 11

Go to Step 14

11

1. Disconnect fuel injector #2 connector.
2. Measure resistance between injector pins A and B (injector)

Is resistance more than the value specified?

8 ohms

Go to Step 12

Go to Step 27

12 | Measure voltage to ground at injector #2 connector terminal B (harness side). Is voltage the same or lower than the value specified? | 0.1 volt | Go to Step 13 | Go to Step 23

13

1. Check terminal contact at PCM connector C2.
2. Repair terminal contact if needed.

Was terminal contact repaired?

--

Go to Powertrain Control Module Diagnosis for Verify Repair

Go to Step 28

14

1. Turn the key to LOCK, reconnect PCM connector C2
2. Disconnect fuel rail connector.
3. Key ON, measure voltage to ground at fuel rail connector (injector side) terminal B.

Is voltage lower than the value specified?

10 volts

Go to Step 15

Go to Step 24

15

1. Disconnect fuel injector #2 connector.
2. Measure resistance to ground at fuel rail connector (injector side) terminal B.

Is resistance more than the value specified?

10K ohms

Go to Step 16

Go to Step 25

16 | Measure resistance between injector #2 pins A and B (injector). Is resistance more than the value specified? | 25 ohms | Go to Step 27 | Go to Step 26
17 | Repair short to ground in the injector 2, 3, 5, 8 Ignition feed circuit between fuse and fuel rail connector. Is the repair complete? | -- | Go to Powertrain Control Module Diagnosis for Verify Repair | --
18 | Repair short to ground in the injector 2, 3, 5, 8 Ignition feed circuit between fuel rail connector and injector connector that low resistance was measured on. Is the repair complete? | -- | Go to Powertrain Control Module Diagnosis for Verify Repair | --
19 | Replace the injector fuse and retest for DTCs. Is the repair complete? | -- | Go to Powertrain Control Module Diagnosis for Verify Repair | --
20 | Repair open in the injector 2, 3, 5, 8 Ignition feed circuit between splice and fuel rail connector. Is the repair complete? | -- | Go to Powertrain Control Module Diagnosis for Verify Repair | --
21 | Repair open in the injector 2, 3, 5, 8 Ignition feed circuit between INJ 1 fuse and fuel rail connector or repair poor terminal contact at fuse. Is the repair complete? | -- | Go to Powertrain Control Module Diagnosis for Verify Repair | --
22 | Repair open in the injector 2, 3, 5, 8 Ignition feed circuit between splice and fuel injector #2. Is the repair complete? | -- | Go to Powertrain Control Module Diagnosis for Verify Repair | --
23 | Repair short to voltage on the injector 2 ignition control circuit. Is the repair complete? | -- | Go to Powertrain Control Module Diagnosis for Verify Repair | --
24 | Repair open or short to ground in the injector 2 ignition control circuit between fuel rail connector and PCM. Is the repair complete? | -- | Go to Powertrain Control Module Diagnosis for Verify Repair | --
25 | Repair short to ground in the injector 2 ignition control circuit between fuel rail connector and injector #2. Is the repair complete? | -- | Go to Powertrain Control Module Diagnosis for Verify Repair | --
26 | Repair open in the injector 2 ignition control circuit between fuel rail connector and injector #2. Is the repair complete? | -- | Go to Powertrain Control Module Diagnosis for Verify Repair | --
27 | Replace the fuel injector. Refer to Fuel Injector Replacement . Is the replacement complete? | -- | Go to Powertrain Control Module Diagnosis for Verify Repair | --
28 | Replace the PCM. Refer to PCM Replacement/Programming . Is the replacement complete? | -- | Go to Powertrain Control Module Diagnosis for Verify Repair | --