Fuel Injector Circuit Diagnosis
Diagnostic Instructions
Diagnostic Fault Information
Circuit
|
Short to Ground
|
Open/High Resistance
|
Short to Voltage
|
Signal Performance
|
Ignition voltage - fuse to splice
|
1
|
2
|
-
|
-
|
Ignition voltage - splice to injector
|
1
|
P0201 00, P0202 00, P0203 00 or P0204 00
|
-
|
-
|
Control (fuel injector 1)
|
P0201 00
|
P0201 00
|
P0262 00
|
-
|
Control (fuel injector 2)
|
P0202 00
|
P0202 00
|
P0265 00
|
-
|
Control (fuel injector 3)
|
P0203 00
|
P0203 00
|
P0268 00
|
-
|
Control (fuel injector 4)
|
P0204 00
|
P0204 00
|
P0271 00
|
-
|
1. Open fuse, cranks no start
2. Cranks no start
|
|
|
Circuit/System Description
The engine control module (ECM) enables the appropriate fuel
injector pulse for each cylinder. Ignition voltage is supplied to
the fuel injectors. The ECM controls each fuel injector by
grounding the control circuit via a solid state device called a
driver.
Reference Information
Schematic Reference
Engine Controls Schematics
Connector End View Reference
Component Connector End Views
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Special Tools
EL 35616-E GM-Approved Terminal Test Kit
Includes J 35616-200 Test Light Probe Kit
For equivalent regional tools, refer to
Special Tools .
Circuit/System Testing
1. |
Ignition OFF, disconnect the
harness connector at the appropriate fuel injector listed
below: |
2. |
Ignition ON, verify that a
test lamp illuminates between the appropriate Q17 Fuel Injector
ignition circuit terminal 1 (LDE/LLU) or circuit terminal A (2H0)
and ground. |
⇒ |
If the test lamp does not illuminate, test the
ignition circuit for a short to ground or an open/high resistance.
If the circuit tests normal and the ignition circuit fuse is open,
test or replace the Q17 Fuel Injector. |
3. |
Ignition OFF, connect a J
35616-200 Test Light Probe Kit between the K20 Engine
Control Module control circuit terminal 2 (LDE/LLU) or B (2H0) and
the ignition circuit terminal 1 (LDE/LLU) or circuit terminal A
(2H0) of each Q17 Fuel Injector one at a time. |
4. |
Engine cranking, the test lamp
should flash for each injector. |
⇒ |
If the test lamp is always ON, test the
appropriate K20 Engine Control Module control circuit for a short
to ground. If the circuit tests normal, replace the K20 Engine
Control Module. |
⇒ |
If the test lamp is always OFF, test the
appropriate K20 Engine Control Module control circuit for a short
to voltage or an open/high resistance. If the circuit tests normal,
replace the K20 Engine Control Module. |
5. |
If all circuits test normal,
test or replace the appropriate Q17 Fuel Injector. Refer to
Fuel Injector Diagnosis . |
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic
procedure.
|