DTC P0480-P0482 or P0691-P0696
|
|
DTC P0480-P0482 or P0691-P0696
|
DTC P0480 00
Cooling Fan Relay 1 Control Circuit
DTC P0481 00
Cooling Fan Relay 2 Control Circuit
DTC P0482 00
Cooling Fan Relay 3 Control Circuit
DTC P0691 00
Cooling Fan Relay 1 Control Circuit Low Voltage
DTC P0692 00
Cooling Fan Relay 1 Control Circuit High Voltage
DTC P0693 00
Cooling Fan Relay 2 Control Circuit Low Voltage
DTC P0694 00
Cooling Fan Relay 2 Control Circuit High Voltage
DTC P0695 00
Cooling Fan Relay 3 Control Circuit Low Voltage
DTC P0696 00
Cooling Fan Relay 3 Control Circuit High Voltage
|
Diagnostic Fault Information
|
Cooling Fan Left High Speed Relay
|
Circuit
|
Short to Ground
|
High Resistance
|
Open
|
Short to Voltage
|
Signal Performance
|
Relay Coil Ignition
|
P0691 00
|
P0691 00
|
P0480 00
|
-
|
-
|
Relay Switch B+
|
1
|
1
|
1
|
-
|
-
|
Relay Coil Control
|
P0691 00
|
P0691 00
|
P0480 00
|
P0692 00
|
-
|
Relay Output Control
|
1
|
1
|
1
|
2
|
-
|
1. Low and medium speed fan inoperative without a DTC.
2. Medium speed fan always ON without a DTC.
|
Cooling Fan Left Low Speed Relay, Cooling Fan Speed Control Relay and Cooling Fan Right Low Speed Relay
|
Circuit
|
Short to Ground
|
High Resistance
|
Open
|
Short to Voltage
|
Signal Performance
|
Relay Coil Ignition
|
P0693 00
|
P0693 00
|
P0481 00
|
-
|
-
|
Relay Switch B+
|
1
|
1
|
1
|
-
|
-
|
Relay Coil Control
|
P0693 00
|
P0693 00
|
P0481 00
|
P0694 00
|
-
|
Relay Output Control
|
1
|
1
|
1
|
2
|
-
|
1. Fans inoperative without a DTC.
2. Medium speed fan always ON without a DTC.
|
Cooling Fan Medium Speed Relay
|
Circuit
|
Short to Ground
|
High Resistance
|
Open
|
Short to Voltage
|
Signal Performance
|
Relay Coil Ignition
|
P0695 00
|
P0695 00
|
P0482 00
|
-
|
-
|
Relay Switch B+
|
1
|
1
|
1
|
-
|
-
|
Relay Coil Control
|
P0695 00
|
P0695 00
|
P0482 00
|
P0696 00
|
-
|
Relay Output Control
|
1
|
1
|
1
|
2
|
-
|
1. High speed fan inoperative without a DTC.
2. High speed fan always ON without a DTC.
|
|
Circuit/System Description
|
The engine control module (ECM) commands the fan ON in either high speed, medium speed, or low speed, depending on cooling requirements. In low speed, the fan is turned ON at a reduced speed. In medium speed, the fans are turned ON at a higher reduced speed. In high speed, the fans are turned ON at full speed. In low speed operation, the ECM provides ground to ECM terminal 94 X2. The cooling fan relay activates and provides ground to the coil of the cooling fan left high speed relay. The cooling fan speed control relay remains inactive because ECM terminal 90 X2 is not grounded. The cooling fan left high speed relay provides power to the engine cooling fan right through engine cooling fan left and the internal fan resistor of engine cooling fan right.
In medium speed operation, the ECM provides ground to ECM terminal 90 X2. The cooling fan left low speed, cooling fan speed control relay and the cooling fan right low speed relay are activated. The internal fan resistor of the engine cooling fan left is provided with power through the cooling fan left low speed relay. The cooling fan speed control relay is active and therefore the engine cooling fan left terminal 3 is directly shorted to ground. The cooling fan right low speed relay is active and provides power to the internal resistor of the engine cooling fan right. The engine cooling fan right terminal 3 is directly shorted to ground. Both fans runs with medium speed.
In high speed operation, the ECM provides ground to ECM terminals 90 X2, 91 X2 and 94 X2. Cooling fan left high speed relay, cooling fan medium speed 1 relay, cooling fan left low speed relay, cooling fan speed control relay and cooling fan right low speed relay are activated. Power is now provided to both cooling fan terminals 1. The engine cooling fan relay left is directly shorted to ground through the cooling fan speed control relay. The engine cooling fan right is directly shorted to ground. In this constellation both fans run without resistor.
|
Conditions for Running the DTC
|
|
•
|
The ignition voltage is between 8-18 V.
|
|
•
|
The engine is running greater than or equal to 400 RPM.
|
|
Conditions for Setting the DTC
|
P0480 00
The ECM detects a malfunction on the cooling fan relay 1 control circuit.
P0481 00
The ECM detects a malfunction on the cooling fan relay 2 control circuit.
P0482 00
The ECM detects a malfunction on the cooling fan relay 3 control circuit.
P0691 00
The ECM detects a short to ground on the cooling fan relay 1 control circuit.
P0692 00
The ECM detects a short to voltage on the cooling fan relay 1 control circuit.
P0693 00
The ECM detects a short to ground on the cooling fan relay 2 control circuit.
P0694 00
The ECM detects a short to voltage on the cooling fan relay 2 control circuit.
P0695 00
The ECM detects a short to ground on the cooling fan 3 control circuit.
P0696 00
The ECM detects a short to voltage on the cooling fan relay 3 control circuit.
|
Action Taken When the DTC Sets
|
DTCs P0691 00, P0692 00, P0693 00, P0694 00, P0695 00 and P0696 00 are Type B DTCs.
|
Conditions for Clearing the DTC
|
DTCs P0691 00, P0692 00, P0693 00, P0694 00, P0695 00 and P0696 00 are Type B DTCs.
Schematic Reference
Engine Cooling Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
Cooling Fan Description and Operation (Diesel)
Cooling Fan Description and Operation (LDK/A20NHT, LBW/A28NER, LAU/A28NET )
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References
for scan tool information
|
Circuit/System Verification
|
|
1.
|
Command the Cooling Fan Relay 1 ON and OFF with a scan tool. The clicking sound of the relay should be heard when changing between the commanded states.
|
|
2.
|
If the relay does not operate correctly, refer to P0480 00, P0691 00 and P0692 00.
|
|
3.
|
Command the Cooling Fan Relay 2 ON and OFF with a scan tool. The clicking sound of the relay should be heard when changing between the commanded states.
|
|
4.
|
If the relay does not operate correctly, refer to P0481 00, P0693 00 and P0694 00.
|
|
5.
|
Command the Cooling Fan Relay 3 ON and OFF with a scan tool. The clicking sound of the relay should be heard when changing between the commanded states.
|
|
6.
|
If the relay does not operate correctly, refer to P0482 00, P0695 00 and P0696 00.
|
P0480 00, P0691 00 and P0692 00
|
1.
|
Ignition OFF, disconnect the KR20J Cooling Fan Left High Speed Relay.
|
|
2.
|
Ignition ON, verify that a test lamp does not illuminate between the relay coil control circuit terminal 2 and ground.
|
|
3.
|
If the test lamp illuminates, test the relay coil control circuit for a short to voltage. If the circuit tests normal, replace the K20 Engine Control Module.
|
|
4.
|
Ignition OFF, disconnect the harness connector X2 at the K20 Engine Control Module. Test for an infinite resistance between the relay coil control circuit terminal 2 and ground.
|
|
5.
|
If less than the specified value, test the relay coil control circuit for a short to ground.
|
|
6.
|
Test for less than 5.0 Ω between relay coil control circuit terminal 2 and K20 Engine Control Module terminal 94 X2.
|
|
7.
|
If greater than the specified value, test the relay coil control circuit for an open/high resistance.
|
|
8.
|
Test for 70-110 Ω between 85 and 86 of the KR20J Cooling Fan Left High Speed Relay.
|
|
9.
|
If the resistance is not within the specified range, replace the KR20J Cooling Fan Left High Speed Relay.
|
|
10.
|
If all circuit tests normal, replace the K20 Engine Control Module.
|
P0481 00, P0693 00 and P0694 00
|
1.
|
Ignition OFF, disconnect the following cooling fan relay.
|
|
|
•
|
KR20L Cooling Fan Speed Control 2 Relay
|
|
|
•
|
KR20G Cooling Fan Left Low Speed Relay
|
|
|
•
|
KR20H Cooling Fan Right Low Speed Relay
|
|
2.
|
|
Note
|
|
The following test must performed on all three cooling fan relays.
|
Ignition ON, verify that a test lamp does not illuminate between the relay coil control circuit terminal 85 and ground.
|
|
3.
|
If the test lamp illuminates, test the relay coil control circuit for a short to voltage. If the circuit tests normal, replace the K20 Engine Control Module.
|
|
4.
|
Ignition OFF, disconnect the K20 Engine Control Module. Test for an infinite resistance between the relay coil control circuit terminal 85 and ground.
|
|
5.
|
If less than the specified value, test the relay coil control circuit for a short to ground.
|
|
6.
|
Test for less than 5.0 Ω between relay coil control circuit terminal 85 and K20 Engine Control Module terminal 90 X2.
|
|
7.
|
If greater than the specified value, test the relay coil control circuit for an open/high resistance.
|
|
8.
|
Test for 70-110 Ω between terminals 85 and 86 of the KR20G Cooling Fan Left Low Speed Relay.
|
|
9.
|
If the resistance is not within the specified range, replace the KR20G Cooling Fan Left Low Speed Relay.
|
|
10.
|
If all circuit tests normal, replace the K20 Engine Control Module.
|
P0482 00, P0695 00 and P0696 00
|
1.
|
Ignition OFF, disconnect the KR20A Cooling Fan Medium Speed 1 Relay.
|
|
2.
|
Ignition ON, verify that a test lamp does not illuminate between the relay coil control circuit terminal 2 and ground.
|
|
3.
|
If the test lamp illuminates, test the relay coil control circuit for a short to voltage. If the circuit tests normal, replace the K20 Engine Control Module.
|
|
4.
|
Ignition OFF, disconnect the K20 Engine Control Module. Test for an infinite resistance between the relay coil control circuit terminal 2 and ground.
|
|
5.
|
If less than the specified value, test the relay coil control circuit for a short to ground.
|
|
6.
|
Test for less than 5.0 Ω between relay coil control circuit terminal 2 and K20 Engine Control Module terminal 91 X2.
|
|
7.
|
If greater than the specified value, test the relay coil control circuit for an open/high resistance.
|
|
8.
|
Test for 70-110 Ω between terminals 85 and 86 of the KR20A Cooling Fan Medium Speed 1 Relay.
|
|
9.
|
If the resistance is not within the specified range, replace the KR20A Cooling Fan Medium Speed 1 Relay.
|
|
10.
|
If all circuit tests normal, replace the K20 Engine Control Module.
|
Dynamic Test
|
1.
|
Ignition OFF, disconnect the applicable relay.
|
|
2.
|
Test for 70-110 Ω between terminals 85 and 86 or 1 and 2 of the relay.
|
|
3.
|
If the resistance is not within the specified range, replace the relay.
|
|
4.
|
Test for infinite resistance between the following terminals:
|
|
|
•
|
If not the specified value, replace the relay.
|
|
5.
|
Install a 20 A fused jumper wire between relay terminal 85 or 2 and 12 V. Install a jumper wire between relay terminal 86 or 1 and ground. Test for less than 2 Ω between terminals 30 or 3 and 87 or 5.
|
|
6.
|
If greater than the specified value, replace the relay.
|
Perform the
Diagnostic Repair Verification
after completing the diagnostic procedure.
|
1.
|
Ignition ON, verify with a scan tool that the ECM is not commanding fan activation.
|
|
2.
|
Ignition ON, observe that the fan is not activated.
|
|
3.
|
Ignition ON, verify with a scan tool that the ECM is not commanding fan activation. Ignition ON, observe that the fan is not activated.
|
