Cooling Fan Inoperative - Auxiliary A/C Cooling Low Speed
Step | Action | Yes | No |
|---|---|---|---|
1 | Did you perform the Engine Cooling Diagnostic System Check? | Go to Step 2 | |
2 |
Does the auxiliary engine coolant fan #1 and auxiliary engine coolant fan #2 operate at low speed? | Go to Step 3 | |
3 |
Notice: Installation of the proper relay is critical. If an enhanced relay -- equipped with a diode -- is installed into a position requiring a standard relay -- equipped without a diode -- excessive current will damage any components associated with the relay or its associated circuits. Did you find and correct the condition? | Go to Step 11 | Go to Step 4 |
4 |
Notice: Installation of the proper relay is critical. If an enhanced relay -- equipped with a diode -- is installed into a position requiring a standard relay -- equipped without a diode -- excessive current will damage any components associated with the relay or its associated circuits. Test circuit F2l of the fan control relay K87 connector for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 11 | Go to Step 5 |
5 |
Notice: Installation of the proper relay is critical. If an enhanced relay -- equipped with a diode -- is installed into a position requiring a standard relay -- equipped without a diode -- excessive current will damage any components associated with the relay or its associated circuits. Does the test lamp illuminate? | Go to Step 8 | Go to Step 6 |
6 | Test circuit U4 of the K87 relay for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 11 | Go to Step 7 |
7 | Refer to Diagnostic Starting Point in HVAC Systems-Automatic. Did you complete the repair? | Go to Step 11 | -- |
8 |
Notice: Installation of the proper relay is critical. If an enhanced relay -- equipped with a diode -- is installed into a position requiring a standard relay -- equipped without a diode -- excessive current will damage any components associated with the relay or its associated circuits. Test circuit AM12 of the fan control relay K87 connector for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 11 | Go to Step 9 |
9 | Inspect for poor connections at the harness connector of the fan control relay K87. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 11 | Go to Step 10 |
10 |
Notice: Installation of the proper relay is critical. If an enhanced relay -- equipped with a diode -- is installed into a position requiring a standard relay -- equipped without a diode -- excessive current will damage any components associated with the relay or its associated circuits. Replace the fan control relay K87. Did you complete the repair? | Go to Step 11 | -- |
11 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 2 |
Cooling Fan Inoperative - Auxiliary A/C Cooling High Speed
Step | Action | Yes | No |
|---|---|---|---|
1 | Did you perform the Engine Cooling Diagnostic System Check? | Go to Step 2 | |
2 |
Does the Auxiliary fan #1 and Auxiliary fan #2 operate at high speed? | Go to Step 4 | Go to Step 3 |
3 | Inspect circuit XM10 of the K28 fan control relay for an open. Notice: Installation of the proper relay is critical. If an enhanced relay -- equipped with a diode -- is installed into a position requiring a standard relay -- equipped without a diode -- excessive current will damage any components associated with the relay or its associated circuits. Replace the fan control relay K28 if these circuits are OK. Did you complete the repair? | Go to Step 5 | -- |
4 |
Did you complete the repair? | Go to Step 5 | -- |
5 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 2 |
Cooling Fan Inoperative - Auxiliary All Fans Inoperative
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Engine Cooling Schematics DEFINITION: The cooling fan and both auxiliary coolant fans are inoperative. | |||
1 | Did you perform the Engine Cooling Diagnostic System Check? | Go to Step 2 | |
2 |
Does the low speed fans turn on approximately 100°C (212°F)? | Go to Testing for Intermittent Conditions and Poor Connections | Go to Step 3 |
3 |
Does the low speed fans turn ON? | Go to Step 7 | Go to Step 4 |
4 |
Does the test lamp illuminate? | Go to Step 5 | Go to Step 14 |
5 | Install a test lamp between circuit A6 and circuit XP3 of the K26 relay. Does the test lamp illuminate? | Go to Step 6 | Go to Step 13 |
6 | With a test lamp connected to a good ground, probe circuit A222 of the K26 relay. Does the test lamp illuminate. | Go to Step 18 | Go to Step 8 |
7 |
Does the cooling fans turn ON. | Go to Step 24 | Go to Step 12 |
8 | Inspect circuit A221, A222, or A223 for a short to ground. Refer to Testing for Short to Ground in Wiring Systems. Did you find and correct the condition? | Go to Step 26 | Go to Step 9 |
9 |
Does the test lamp illuminate? | Go to Step 15 | Go to Step 10 |
10 | Inspect the auxiliary coolant fan 1 for a short to ground. Refer to Testing for Short to Ground in Wiring Systems. Did you find and correct the condition? | Go to Step 20 | Go to Step 11 |
11 |
Does the test lamp illuminate? | Go to Step 16 | Go to Step 22 |
12 | Inspect circuit XP30 of the primary cooling fan temperature switch for an open or high resistance. Testing for Intermittent Conditions and Poor Connections and Testing for Continuity in Wiring Systems. Did you find and correct the condition? | Go to Step 26 | Go to Step 17 |
13 | Repair circuit XP3 of the K26 relay for an open or high resistance. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 26 | -- |
14 | Repair circuit A6 of the K26 relay for an open, high resistance or short to ground. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 26 | -- |
15 | Repair circuit A1, AM12 or AM13 of the K26 relay for a short to ground. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 26 | -- |
16 | Repair circuit AP1, AP2, AP3, or XU2 of the K26 relay for a short to ground. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 26 | -- |
17 | Repair circuit F600 of the primary cooling fan temperature switch for an open or high resistance. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 26 | -- |
18 | Inspect for poor connections at the K26 relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find the problem? | Go to Step 26 | Go to Step 19 |
19 |
Notice: Installation of the proper relay is critical. If an enhanced relay -- equipped with a diode -- is installed into a position requiring a standard relay -- equipped without a diode -- excessive current will damage any components associated with the relay or its associated circuits. Replace the fan control relay K26. Did you complete the repair? | Go to Step 26 | -- |
20 | Inspect for poor connections at the auxiliary coolant fan 1. Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find the problem? | Go to Step 26 | Go to Step 21 |
21 | Replace the auxiliary coolant fan 1. Refer to Auxiliary Engine Coolant Fan and Fan Motor Replacement . Did you complete the repair? | Go to Step 26 | -- |
22 | Inspect for poor connections at the auxiliary water pump. Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find the problem? | Go to Step 26 | Go to Step 23 |
23 | Replace the auxiliary water pump. Refer to Auxiliary Water Pump Replacement . Did you complete the repair? | Go to Step 26 | -- |
24 | Inspect for poor connections at the primary cooling fan temperature switch. Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find the problem? | Go to Step 26 | Go to Step 25 |
25 | Replace the primary cooling fan temperature switch . Refer to Engine Cooling Fan Control Switch Replacement . Did you complete the repair? | Go to Step 26 | -- |
26 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 2 |
Cooling Fan Inoperative - Auxiliary Auxiliary Fan 1 and or 2 Inoperative
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Engine Cooling Schematics DEFINITION: The auxiliary coolant fan 1 and or 2 are inoperative on low speed, high speed or both. | |||
1 | Did you perform the Engine Cooling Diagnostic System Check? | Go to Step 2 | |
2 |
Are both auxiliary coolant fans inoperative? | Go to Step 18 | Go to Step 3 |
3 | With the jumper wire still installed between pin 1 and pin 6 . Is the auxiliary coolant fan 2 inoperative? | Go to Step 15 | Go to Step 4 |
4 |
Does the auxiliary coolant fan 1 and auxiliary coolant fan 2 operate in high speed above 105°C (221°F)? | Go to Testing for Intermittent Conditions and Poor Connections | Go to Step 5 |
5 | With the vehicle still running above 105°C (221°F). Are both fans operating at low speed. | Go to Step 13 | Go to Step 6 |
6 |
Is the auxiliary coolant fan 1 inoperative? | Go to Step 7 | Go to Step 9 |
7 |
Does the test lamp illuminate? | Go to Step 8 | Go to Step 28 |
8 | Install a test lamp between circuit XM123 and circuit X30 of the K52 relay. Does the test lamp illuminate? | Go to Step 45 | Go to Step 29 |
9 |
Does the test lamp illuminate? | Go to Step 10 | Go to Step 30 |
10 | Install a test lamp between circuit X400 and XM124 of the K28 relay. Does the test lamp illuminate? | Go to Step 11 | Go to Step 31 |
11 | With a test lamp connected to a good ground, probe circuit A14 at the K28 relay. Does the test lamp illuminate? | Go to Step 12 | Go to Step 32 |
12 | Connect a test lamp between circuit A14 and circuit AM4. Does the test lamp illuminate. | Go to Step 43 | Go to Step 33 |
13 |
Does the auxiliary coolant fan 1 and coolant fan 2 operate at high speed? | Go to Step 39 | Go to Step 14 |
14 | Inspect circuit XM122 of the secondary cooling fan temperature switch for an open or high resistance. Refer to Testing for Continuity in Wiring Systems. Did you find and correct the condition? | Go to Step 49 | Go to Step 34 |
15 | Disconnect the auxiliary coolant fan 2. Does the auxiliary coolant fan 1 turn OFF? | Go to Step 25 | Go to Step 16 |
16 | Remove the fan control relay K52. Does the auxiliary coolant fan 1 turn OFF? | Go to Step 17 | Go to Step 35 |
17 | Inspect circuit AM3, AM4 and AM5 of the K52 relay for a short to ground. Refer to Testing for Short to Ground in Wiring Systems. Did you find and correct the condition? | Go to Step 49 | Go to Step 45 |
18 |
Does the auxiliary coolant fan 1 and coolant fan 2 turn ON? | Go to Step 45 | Go to Step 19 |
19 |
Does the test lamp illuminate? | Go to Step 20 | Go to Step 36 |
20 | Install a 30 amp fused jumper wire between circuit A222 and circuit AM1 of the K26 relay. Does the auxiliary coolant fan 1 and coolant fan 2 turn ON? | Go to Step 47 | Go to Step 21 |
21 |
Does the test lamp illuminate? | Go to Step 22 | Go to Step 37 |
22 | Install a 30 amp fused jumper wire between circuit AM13 and circuit XU3 of the cooling fan 1 connector. Does the auxiliary coolant fan 2 operate at high speed? | Go to Step 41 | Go to Step 23 |
23 |
Does the test lamp illuminate? | Go to Step 24 | Go to Step 27 |
24 | Inspect circuit F4 of the auxiliary coolant fan 2 for an open. Did you find and correct the condition? | Go to Step 49 | Go to Step 25 |
25 | Inspect for poor connections at the auxiliary coolant fan 2. Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find the problem? | Go to Step 49 | Go to Step 26 |
26 | Replace the auxiliary coolant fan 2. Refer to Auxiliary Engine Coolant Fan and Fan Motor Replacement . Did you complete the repair? | Go to Step 49 | -- |
27 | Inspect circuit AM5 and circuit AM3 of the auxiliary coolant fan 2 for an open or high resistance. Did you find and correct the condition? | Go to Step 49 | Go to Step 38 |
28 | Repair circuit X30, X68, X67 or X868 of the K52 relay for an open or high resistance or short to ground. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 49 | -- |
29 | Repair circuit XM123 of the K52 relay for an open or high resistance. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 49 | -- |
30 | Repair circuit X400 of the K28 relay for an open, high resistance or short to ground. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 49 | -- |
31 | Repair circuit XM124 of the K28 relay for an open or high resistance. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 49 | -- |
32 | Repair circuit A14 of the K28 relay for an open or high resistance or a short to ground. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 49 | -- |
33 | Repair circuit AM4 of the K28 relay for an open or high resistance. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 49 | -- |
34 | Repair circuit F60 of the secondary cooling fan temperature switch for an open or high resistance. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 49 | -- |
35 | Repair circuit XU3 of the K52 reley for a shart to ground. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 49 | -- |
36 | Repair circuit A222 of the K26 reley for an open or high resistance. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 49 | -- |
37 | Repair circuit AM13 or AM1 of the auxiliary coolant fan 1 for an open or high resistance. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 49 | -- |
38 | Repair circuit XU3 of the auxiliary coolant fan 1 for an open or high resistance. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 49 | -- |
39 | Inspect for poor connections at the secondary cooling fan temperature switch. Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find the problem? | Go to Step 49 | Go to Step 40 |
40 | Replace the secondary cooling fan temperature switch . Refer to Engine Cooling Fan Control Switch Replacement . Did you complete the repair? | Go to Step 49 | -- |
41 | Inspect for poor connections at the auxiliary coolant fan 1. Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find the problem? | Go to Step 49 | Go to Step 42 |
42 | Replace the auxiliary coolant fan 1. Refer to Auxiliary Engine Coolant Fan and Fan Motor Replacement . Did you complete the repair? | Go to Step 49 | -- |
43 | Inspect for poor connections at the K28 relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find the problem? | Go to Step 49 | Go to Step 44 |
44 |
Notice: Installation of the proper relay is critical. If an enhanced relay -- equipped with a diode -- is installed into a position requiring a standard relay -- equipped without a diode -- excessive current will damage any components associated with the relay or its associated circuits. Replace the fan control relay K28. Did you complete the repair? | Go to Step 49 | -- |
45 | Inspect for poor connections at the K52 relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find the problem? | Go to Step 49 | Go to Step 46 |
46 |
Notice: Installation of the proper relay is critical. If an enhanced relay -- equipped with a diode -- is installed into a position requiring a standard relay -- equipped without a diode -- excessive current will damage any components associated with the relay or its associated circuits. Replace the fan control relay K52. Did you complete the repair? | Go to Step 49 | -- |
47 | Inspect for poor connections at the K26 relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find the problem? | Go to Step 49 | Go to Step 48 |
48 |
Notice: Installation of the proper relay is critical. If an enhanced relay -- equipped with a diode -- is installed into a position requiring a standard relay -- equipped without a diode -- excessive current will damage any components associated with the relay or its associated circuits. Replace the fan control relay K26. Did you complete the repair? | Go to Step 49 | -- |
49 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 2 |
