Home ReviewsRefund
Home/Honda/S2000/Honda S2000 AP1 (1999-2003)/Repair manual/Cooling Fan/Fan Controls: Other
Contents Wiring diagrams Section: Cooling Fan All sections

Fan Controls: Other Honda S2000 AP1

Cooling Fan 21 illustrations ~1455 words

2000-2005 Models

SymptomDiagnostic procedureAlso check for
Engine overheatsCheck the coolant level Check for any engine coolant leakage (from gaskets, hoses, O-rings, etc.) Check for dirt, leaves, or insects on radiator and A/C condenser. Check for deteriorated coolant. Check for damaged or deformed fan shroud. Inspect the fan motors (see FAN MOTOR TEST ), fan relays (see POWER RELAY TEST ), or radiator fan switch (see RADIATOR FAN SWITCH TEST ). Check the radiator cap (see RADIATOR CAP TEST ). Check for a broken drive belt (see DRIVE BELT INSPECTION ). Check the thermostat (see RADIATOR TEST ). Inspect the water pump (see WATER PUMP INSPECTION Check for plugged or deteriorated radiator hoses. Check for plugged heater core or hoses. Check for a damaged cylinder head gasket.
The radiator fan does not run at allRADIATOR FAN CIRCUIT TROUBLESHOOTING .Cleanliness and tightness of all connectors
The radiator fan does not run for engine cooling, but it runs with the A/C onRADIATOR FAN SWITCH CIRCUIT TROUBLESHOOTING (OPEN) .Cleanliness and tightness of all connectors
The radiator fan runs with the ignition switch ON (II), the A/C off, and the engine coolant temperature below 199°F (93°C)RADIATOR FAN SWITCH CIRCUIT TROUBLESHOOTING (SHORT) .Cleanliness and tightness of all connectors
The A/C condenser fan does not run at all (but the radiator fan runs with the A/C on)A/C CONDENSER FAN CIRCUIT TROUBLESHOOTING ).HVAC DTCs (see GENERAL TROUBLESHOOTING INFORMATION ) Cleanliness and tightness of all connectors
Both the radiator fan and the A/C condenser fan do not run with the A/C on (but the A/C compressor runs with the A/C on)RADIATOR AND A/C CONDENSER FAN COMMON CIRCUIT TROUBLESHOOTING .HVAC DTCs (see GENERAL TROUBLESHOOTING INFORMATION ) Cleanliness and tightness of all connectors

SYMPTOM TROUBLESHOOTING TABLE

2006-2009 Model

SymptomDiagnostic procedureAlso check for
Engine overheatsCheck the coolant level. Check for any engine coolant leakage (from gaskets, hoses, O-rings, etc.). Check for dirt, leaves, or insects on radiator and A/C condenser. Check for deteriorated coolant. Check for a damaged or deformed fan shroud. Inspect the fan motors (see FAN MOTOR TEST ) or fan relays (see POWER RELAY TEST ). Check the radiator cap (see RADIATOR CAP TEST ). Check the thermostat (see THERMOSTAT TEST ). Inspect the water pump (see WATER PUMP INSPECTION ). Check for a plugged or deteriorated radiator hoses. Check for plugged heater core or hoses. Check for a damaged cylinder head gasket.
The radiator fan does not run at allRADIATOR FAN CIRCUIT TROUBLESHOOTING .PGM-FI DTCs (see GENERAL TROUBLESHOOTING INFORMATION ). Cleanliness and tightness of all connectors
The radiator fan does not run for engine cooling, but it runs with the A/C onRADIATOR FAN SWITCH CIRCUIT TROUBLESHOOTING (OPEN) .Cleanliness and tightness of all connectors
The radiator fan runs with the ignition switch ON (II), the A/C off, and the engine coolant temperature below 199°F (93°C)Radiator fan switch circuit troubleshooting (Short) (see RADIATOR FAN SWITCH CIRCUIT TROUBLESHOOTING (SHORT) .Cleanliness and tightness of all connectors
The A/C condenser fan does not run at all (but the radiator fan runs with the A/C on)A/C CONDENSER FAN CIRCUIT TROUBLESHOOTING .HVAC DTCs (see GENERAL TROUBLESHOOTING INFORMATION ) Cleanliness and tightness of all connectors
Both the radiator fan and the A/C condenser fan do not run with the A/C on (but the A/C compressor runs with the A/C on)RADIATOR AND A/C CONDENSER FAN COMMON CIRCUIT TROUBLESHOOTING .HVAC DTCs (see GENERAL TROUBLESHOOTING INFORMATION ) Cleanliness and tightness of all connectors

SYMPTOM TROUBLESHOOTING TABLE

Scheme 2

Scheme 2: Circuit Diagram
Scheme 2: Circuit Diagram

Scheme 3

Scheme 3
Scheme 3

Scheme 4

Scheme 4: 2000-2005 Models
Scheme 4: 2000-2005 Models

Scheme 5

Scheme 5
Scheme 5

Scheme 6

Scheme 6
Scheme 6

Scheme 7

Scheme 7
Scheme 7

Scheme 8

Scheme 8
Scheme 8

Scheme 9

Scheme 9
Scheme 9

Scheme 10

Scheme 10
Scheme 10
  1. Check the No. 57 (20 A), No. 41 (100 A), and No. 42 (40 A) fuses in the main under-hood fuse/relay box, and the No. 20 (7.5 A) fuse in the under-dash fuse/relay box. Are the fuses OK? YES - Go to step 2 . NO - Replace the fuse(s) and recheck.
  2. Remove the radiator fan relay from the main under-hood fuse/relay box, and test it (see «POWER RELAY TEST»(ref-221386-S33182512862006022400000) ). Is the relay OK? YES - Go to step 3 . NO - Replace the radiator fan relay.
  3. Measure the voltage between the radiator fan relay 4P socket terminal No. 1 and body ground. Is there battery voltage? YES - Go to step 4 . NO - Replace the main under-hood fuse/relay box.
  4. Connect the radiator fan relay 4P socket terminals No. 1 and No. 2 with a jumper wire. Does the radiator fan run? YES - Go to step 5 . NO - Go to step 6 .
  5. Disconnect the jumper, and turn the ignition switch ON (II). Check for voltage between the radiator fan relay 4P socket terminal No. 3 and body ground. Is there battery voltage? YES - Go to step 9 . NO - Repair an open in the wire between the main under-hood fuse/relay box and under-dash fuse/relay box.
  6. Disconnect the radiator fan motor 2P connector.
  7. Check for continuity between the radiator fan relay 4P socket terminal No. 2 and the radiator fan motor 2P connector terminal No. 2 Is there continuity? YES - Go to step 8 . NO - Repair an open in the wire between the main under-hood fuse/relay box and the radiator fan motor 2P connector terminal No. 2.
  8. Check for continuity between the radiator fan motor 2P connector terminal No. 1 and body ground. Is there continuity? YES - Replace the radiator fan motor. NO - Repair an open in the wire between radiator fan motor 2P connector terminal No. 1 and body ground. If the wire is OK, check for a poor ground at G201.
  9. Turn the ignition switch to LOCK (0).
  10. Disconnect the radiator fan switch 2P connector.
  11. Turn the ignition switch to LOCK (0). Connect the radiator fan switch 2P connector terminals No. 1 and No. 2 with a jumper wire, then turn the ignition switch ON (II). Does the radiator fan run? YES - Replace the radiator fan switch. NO - Go to step 12 .
  12. Turn the ignition switch to LOCK (0). Remove the jumper wire, then turn the ignition switch ON (II). Measure the voltage between the radiator fan switch 2P connector terminal No. 2 and body ground. Is there battery voltage? YES - Repair an open in the wire between radiator fan switch 2P connector terminal No. 1 and body ground. If the wire is OK, check for a poor ground at G301. NO - Repair an open in the wire between the radiator fan switch 2P connector terminal No. 2 and the main under-hood fuse/relay box.

Scheme 11

Scheme 11: 2006-2009 Model
Scheme 11: 2006-2009 Model

Scheme 12

Scheme 12
Scheme 12

Scheme 13

Scheme 13
Scheme 13

Scheme 14

Scheme 14
Scheme 14

Scheme 15

Scheme 15
Scheme 15

Scheme 16

Scheme 16
Scheme 16
  1. Check for the PGM-FI DTCs. See «GENERAL TROUBLESHOOTING INFORMATION»(ref-221338-S00993557042006022400000) . Is DTC P2183, P2184 and/or P2185 indicated? YES - Do the appropriate troubleshooting, then recheck. NO - Go to step 2 .
  2. 2006-2007 models: Check the No. 57 (20 A), No. 41 (100 A), and No. 42 (40 A) fuses in the main under-hood fuse/relay box, and the No. 20 (7.5 A) fuse in the under-dash fuse/relay box.
  3. 2008-2009 models: Check the No. 57 (30 A), No. 41 (100 A), and No. 42 (40 A) fuses in the main under-hood fuse/relay box, and the No. 20 (7.5 A) fuse in the under-dash fuse/relay box. Are the fuses OK? YES - Go to step 4 . NO - Replace the fuse(s) and recheck.
  4. Remove the radiator fan relay from the main under-hood fuse/relay box, and test it (see «POWER RELAY TEST»(ref-221386-S33182512862006022400000) ). Is the relay OK? YES - Go to step 5 . NO - Replace the radiator fan relay.
  5. Measure the voltage between the radiator fan relay 4P socket terminal No. 1 and body ground. Is there battery voltage? YES - Go to step 6 . NO - Replace the main under-hood fuse/relay box.
  6. Connect the radiator fan relay 4P socket terminals No. 1 and No. 2 with a jumper wire. Does the radiator fan run? YES - Go to step 7 . NO - Go to step 8 .
  7. Disconnect the jumper, and turn the ignition switch ON (II). Check for voltage between the radiator fan relay 4P socket terminal No. 3 and body ground. Is there battery voltage? YES - Go to step 11 . NO - Repair an open in the wire between the main under-hood fuse/relay box and under-dash fuse/relay box.
  8. Disconnect the radiator fan motor 2P connector.
  9. Check for continuity between the radiator fan relay 4P socket terminal No. 2 and the radiator fan motor 2P connector terminal No. 2. Is there continuity? YES - Go to step 10 . NO - Repair an open in the wire between the main under-hood fuse/relay box and the radiator fan motor 2P connector terminal No. 2.
  10. Check for continuity between the radiator fan motor 2P connector terminal No. 1 and body ground. Is there continuity? YES - Replace the radiator fan motor. NO - Repair an open in the wire between radiator fan motor 2P connector terminal No. 1 and body ground. If the wire is OK, check for a poor ground at G201.
  11. Turn the ignition switch to LOCK (0), then check for continuity between the radiator fan relay 4P socket terminal No. 4 and the ECM connector terminal E12. Is there continuity? YES - Update the ECM if it does not have the latest software (see «UPDATING THE ECM»(ref-221338-S06618208692006022400000) ), or substitute a known-good ECM (see «SUBSTITUTING THE ECM»(ref-221338-S28616532062006022400000) ), then recheck. If the symptom/indication goes away with a known good ECM, replace the original ECM (see «ECM REPLACEMENT»(ref-221329-S30667517252006022400000) ). NO - Repair an open in the wire between the ECM connector terminal E12 and the main under-hood fuse/relay box.

Scheme 17

Scheme 17: 2000-2005 Models
Scheme 17: 2000-2005 Models

Scheme 18

Scheme 18
Scheme 18
  1. Disconnect the radiator fan switch 2P connector.
  2. Turn the ignition switch ON (II).
  3. Measure voltage between the radiator fan switch 2P connector terminal No. 2 and body ground. Is there battery voltage? YES - Go to step 4 . NO - Repair an open in the wire between the radiator fan switch 2P connector terminal No. 2 and main under-hood fuse/relay box.
  4. Turn the ignition switch to LOCK (0) , and check for continuity between the radiator fan switch 2P connector terminal No. 1 and body ground. Is there continuity? YES - Replace the radiator fan switch. NO - Repair an open in the wire between the radiator fan switch 2P connector terminal No. 1 and body ground. If the wire is OK, check for a poor ground at G301.

Scheme 19

Scheme 19: 2000-2005 Models
Scheme 19: 2000-2005 Models
  1. Remove the radiator fan relay from the main under-hood fuse/relay box, and test it (see «POWER RELAY TEST»(ref-221386-S33182512862006022400000) ). Is the relay OK? YES - Go to step 2 . NO - Replace the radiator fan relay.
  2. Remove the radiator fan switch, and test it (see «RADIATOR FAN SWITCH TEST»(ref-221327-S40690856972006022400000) ). Is the radiator fan switch OK? YES - Go to step 3 . NO - Replace the radiator fan switch.
  3. Disconnect engine control module (ECM) connector A (32P) and the under-hood fuse/relay box 16P connector.
  4. Check for continuity between the radiator fan switch 2P connector terminal No. 2 and body ground. Is there continuity? YES - Repair a short in the wire between the radiator fan switch 2P connector terminal No. 2 and main under-hood fuse/relay box. NO - Replace the main under-hood fuse/relay box.

Scheme 20

Scheme 20: 2000-2005 Models
Scheme 20: 2000-2005 Models

Scheme 21

Scheme 21
Scheme 21
  1. Remove the radiator fan switch from the radiator (see «RADIATOR FAN SWITCH REPLACEMENT»(ref-221327-S36234350372006022400000) ).
  2. Suspend the radiator fan switch (A) in a container of water as shown below.
  3. Heat the water and check the temperature with a thermometer. Do not let the thermometer (B) touch the bottom of the hot container.
  4. Measure the continuity between terminal No. 1 and terminal No. 2 according to the table below.
  5. Replace if necessary, and install the radiator fan switch (see «RADIATOR FAN SWITCH REPLACEMENT»(ref-221327-S36234350372006022400000) ).

Scheme 22

Scheme 22: 2000-2005 Models
Scheme 22: 2000-2005 Models
  1. Drain the engine coolant (see «COOLANT REPLACEMENT»(ref-221326-S23165940062006022400000) ).
  2. Disconnect the radiator fan switch connector, then remove the radiator fan switch (A).
  3. Install the radiator fan switch with a new O-ring (B).
  4. Refill the radiator with engine coolant, then bleed the air from the cooling system (see step 8 on «COOLANT REPLACEMENT»(ref-221326-S23165940062006022400000) ).

More articles — Fan Controls