Fan Controls — Acura TL IV (2008-2011)

Scheme 1

Scheme 1: Component Location Index

Symptom Troubleshooting Index

Symptom	Diagnostic Procedure	Also check for
Engine overheats	Check the coolant level Check for any engine coolant leakage (from gaskets, hoses, O-rings, etc) Check for dirt, leaves, or insects on the radiator and A/C condenser Check for deteriorated coolant Check for damaged or deformed fan shrouds Check the fan motors for proper direction of operation (blowing air toward the engine) Inspect the fan motors (see FAN MOTOR TEST ) or fan relays A/C condenser fan relay (see POWER RELAY TEST ) Radiator fan relay (see FIVE-TERMINAL TYPE ) Fan control relay (see FIVE-TERMINAL TYPE ) Check the radiator cap (see RADIATOR CAP TEST ) Check the thermostat (see FAN MOTOR 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	Proper radiator and condenser fan control and operation
The radiator fan does not run at high speed	Radiator fan high speed circuit troubleshooting (see RADIATOR FAN HIGH SPEED CIRCUIT TROUBLESHOOTING )	Cleanliness and tightness of all connectors
Both the radiator fan and the A/C condenser fan do not run at low speed	Radiator and A/C condenser fans low speed circuit troubleshooting (see RADIATOR AND A/C CONDENSER FAN LOW SPEED CIRCUIT TROUBLESHOOTING )	Cleanliness and tightness of all connectors
The A/C condenser fan does not run at high speed	A/C condenser fan high speed circuit troubleshooting (see A/C CONDENSER FAN HIGH SPEED CIRCUIT TROUBLESHOOTING )	Cleanliness and tightness of all connectors

TROUBLESHOOTING CHART

Scheme 2

Scheme 2: Without Keyless Access System

Scheme 3

Scheme 3: With Keyless Access System

Without Keyless Access System

Note. Information marked with an asterisk (*1) applies to without SH-AWD ('09 model, (*2) applies to with SH-AWD ('09 model), (*3) applies to without SH-AWD ('09 model), and (*4) applies to with SH-AWD ('10 - 11 model).

Scheme 4

Scheme 4: Without Keyless Access System

Scheme 5

Scheme 6

Scheme 7

Scheme 8

Scheme 9

Scheme 10

Check the No 3-5 (30 A) (*1, *3), (40 A) (*2, *4) fuse, the No 14 (15 A) fuse, and the No 21 (7 5 A) fuse in the under-hood fuse/relay box, and the No 16 (7 5 A) fuse in the driver's under-dash fuse/relay box Are the fuse(s) OK? YES -Reinstall the fuse(s), then go to step 2 NO -Replace the fuse(s) and recheck If the fuse continues to blow, locate and repair the short in the circuit between the under-hood fuse/relay box and the relay circuit board, the under-hood fuse/relay box and the radiator fan motor, the driver's under-dash fuse/relay box connector terminal F26 and the under-hood fuse/relay box connector terminal B8
Disconnect and remove the relay circuit board from the under-hood fuse/relay box, and test it (see «FIVE-TERMINAL TYPE»(/acura/tl/iv-2008-2011/remont/body-electrical/#relays__five-terminal-type) ) Is the relay circuit board OK? YES -Go to step 3 NO -Replace the relay circuit board, then retest (see «UNDER-HOOD FUSE/RELAY BOX»(/acura/tl/iv-2008-2011/remont/body-electrical/#fuserelay-boxes__under-hood-fuserelay-box) ).
Measure the voltage between under-hood fuse/relay box connector terminal C3 and body ground Is there battery voltage? YES -Go to step 4 NO -Replace the under-hood fuse/relay box
Connect under-hood fuse/relay box connector terminals C1 and C3 with a jumper wire Does the radiator fan run at high speed? YES -Go to step 8 NO -Go to step 5
Disconnect the radiator fan motor 2P connector, then test the fan motor (see «FAN MOTOR TEST»(/acura/tl/iv-2008-2011/remont/cooling-system-mechanical/#cooling-system) ) Is the fan motor OK? YES -Go to step 6 NO -Replace the radiator fan motor, then retest
Check for continuity between radiator fan motor 2P connector terminal No 1 and body ground Is there continuity? YES -Go to step 7 NO -Repair open in the wire between radiator fan motor 2P connector terminal No 1 and body ground (G302)
Check for continuity between under-hood fuse/relay box connector terminal C1 and radiator fan motor 2P connector terminal No 2 Is there continuity? YES -Check for poor connections or loose terminals at the under-hood fuse/relay box and the radiator fan motor, the radiator fan motor and body ground (G302) NO -Repair open in the wire between under-hood fuse/relay box connector terminal C1 and radiator fan motor 2P connector terminal No 2
Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
Measure the voltage between under-hood fuse/relay box connector terminal B8 and body ground Is there battery voltage? YES -Go to step 10 NO -Repair open in the wire between driver's under-dash fuse/relay box connector terminal F26 and under-hood fuse/relay box connector terminal B8
Measure the voltage between under-hood fuse/relay box connector terminal B9 and body ground Is there battery voltage? YES -Go to step 11 NO -Check the PGM-FI subrelay If the relay is OK, replace the under-hood fuse/relay box
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
Connect the Honda Diagnostic System (HDS) to the data link connector (DLC) (see step 2 on «GENERAL TROUBLESHOOTING INFORMATION»(/acura/tl/iv-2008-2011/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems) )
Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
Make sure the HDS communicates with the vehicle and the powertrain control module (PCM) If it does not communicate, troubleshoot the DLC circuit (see «DLC CIRCUIT TROUBLESHOOTING»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__dlc-circuit-troubleshooting) )
Jump the SCS line with the HDS, then turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode NOTE: This step must be done to protect the PCM from damage
Disconnect PCM connector A (49P)
Check for continuity between PCM connector terminal A5 and under-hood fuse/relay box connector terminal B10 Is there continuity? YES -Update the PCM if it does not have the latest software (see «ECM/PCM UPDATE»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__ecmpcm-update) ), or substitute a known-good PCM (see «SUBSTITUTING THE ECM/PCM»(/acura/tl/iv-2008-2011/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-ecmpcm) ), then recheck If the symptom/indication goes away with a known-good PCM, replace the original PCM (see «ECM/PCM REPLACEMENT»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__ecmpcm-replacement) ) NO -Repair open the wire between under-hood fuse/relay box connector terminal B10 and PCM connector terminal A5

With Keyless Access System

Note. Information marked with an asterisk (*1) applies to without SH-AWD ('09 model, (*2) applies to with SH-AWD ('09 model), (*3) applies to A/T model without SH-AWD and M/T model with SH-AWD ('10 - 11 model) and (*4) applies to A/T model with SH-AWD ('10 - 11 model).

Check the No 3-5 (30 A) (*1, *3), (40 A) (*2, *4) fuse, the No 14 (15 A) fuse, and the No 21 (7 5 A) fuse in the under-hood fuse/relay box, and the No 16 (7 5 A) fuse in the driver's under-dash fuse/relay box Are the fuse(s) OK? YES -Reinstall the fuse(s), then go to step 2 NO -Replace the fuse(s) and recheck If the fuse continues to blow, locate and repair the short in the circuit between the under-hood fuse/relay box and the relay circuit board, the under-hood fuse/relay box and the radiator fan motor, the driver's under-dash fuse/relay box connector terminal F26 and the under-hood fuse/relay box connector terminal B8
Disconnect and remove the relay circuit board from the under-hood fuse/relay box, and test it (see «FIVE-TERMINAL TYPE»(/acura/tl/iv-2008-2011/remont/body-electrical/#relays__five-terminal-type) ) Is the relay circuit board OK? YES -Go to step 3 NO -Replace the relay circuit board, then retest
Measure the voltage between under-hood fuse/relay box connector terminal C3 and body ground Is there battery voltage? YES -Go to step 4 NO -Replace the under-hood fuse/relay box
Connect under-hood fuse/relay box connector terminals C1 and C3 with a jumper wire Does the radiator fan run at high speed? YES -Go to step 8 NO -Go to step 5
Disconnect the radiator fan motor 2P connector, then test the fan motor (see «FAN MOTOR TEST»(/acura/tl/iv-2008-2011/remont/cooling-system-mechanical/#cooling-system) ) Is the fan motor OK? YES -Go to step 6 NO -Replace the radiator fan motor, then retest
Check for continuity between radiator fan motor 2P connector terminal No 1 and body ground Is there continuity? YES -Go to step 7 NO -Repair open in the wire between radiator fan motor 2P connector terminal No 1 and body ground (G302)
Check for continuity between under-hood fuse/relay box connector terminal C1 and radiator fan motor 2P connector terminal No 2 Is there continuity? YES -Check for poor connections or loose terminals at the under-hood fuse/relay box and the radiator fan motor, the radiator fan motor and body ground (G302) NO -Repair open in the wire between under-hood fuse/relay box connector terminal C1 and radiator fan motor 2P connector terminal No 2
Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
Measure the voltage between under-hood fuse/relay box connector terminal B8 and body ground Is there battery voltage? YES -Go to step 10 NO -Repair open in the wire between driver's under-dash fuse/relay box connector terminal F26 and under-hood fuse/relay box connector terminal B8
Measure the voltage between under-hood fuse/relay box connector terminal B9 and body ground Is there battery voltage? YES -Go to step 11 NO -Check the PGM-FI subrelay If the relay is OK, replace the under-hood fuse/relay box
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
Connect the Honda Diagnostic System (HDS) to the data link connector (DLC) (see step 2 on «GENERAL TROUBLESHOOTING INFORMATION»(/acura/tl/iv-2008-2011/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems) )
Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
Make sure the HDS communicates with the vehicle and the powertrain control module (PCM) If it does not communicate, troubleshoot the DLC circuit (see «DLC CIRCUIT TROUBLESHOOTING»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__dlc-circuit-troubleshooting) )
Jump the SCS line with the HDS, then turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode NOTE: This step must be done to protect the PCM from damage
Disconnect PCM connector A (49P)
Check for continuity between PCM connector terminal A5 and under-hood fuse/relay box connector terminal B10 Is there continuity? YES -Update the PCM if it does not have the latest software (see «ECM/PCM UPDATE»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__ecmpcm-update) ), or substitute a known-good PCM (see «SUBSTITUTING THE ECM/PCM»(/acura/tl/iv-2008-2011/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-ecmpcm) ), then recheck If the symptom/indication goes away with a known-good PCM, replace the original PCM (see «ECM/PCM REPLACEMENT»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__ecmpcm-replacement) ) NO -Repair open the wire between under-hood fuse/relay box connector terminal B10 and PCM connector terminal A5

Fan Controls Acura TL IV