Honda - Accord Prelude 1996 2000

Engine Fan



The radiator cooling fans are electrically operated and mount directly to the radiator.

Never open a radiator cap or cooling system when the coolant temperature is above 100°F (38°C). Avoid physical contact at all times, wear protective clothing and eye protection. Always drain coolant into a sealable container. If spillage occurs take care to clean the spill as quickly as possible.

  1. Note the radio security code and disconnect the negative battery cable.
  3. Detach the electrical connectors and wiring guide brackets from the cooling fans
  5. If additional work space is needed, drain about 3 quarts of coolant from the radiator into a sealable container by loosening the radiator drain plug, then disconnect and plug the upper radiator hose.
  7. Remove the positive battery cable and remove the battery.
  9. Disconnect the wire harness guides from the battery tray.
  11. Remove the ground strap and the relay box bracket from the battery tray.
  13. Remove the battery tray mounting bolts and remove the battery tray.
  15. Remove the wire harness holders from the upper radiator support.
  17. Detach the electrical connectors from the air conditioning compressor clutch.
  19. Remove the fan shroud mounting bolts.
  21. Carefully remove the cooling fan assembly from the vehicle.

Click image to see an enlarged view

Fig. Exploded view of common radiator cooling fans and related components

To install:

  1. The installation is in the reverse order of removal except for the following.
  3. Top off and bleed the cooling system as necessary.
  5. When connecting the battery cables, connect the positive battery cable first, then the negative cable.
  7. Enter the radio security code.
  9. Start the engine and check for coolant leaks and normal operation of the cooling fans.


The electrically operated cooling fans can begin to operate without notice, should an electrical component fail or if a circuit interference occurs. Always keep fingers, hands and objects clear of the cooling fans as unexpected operation of the cooling fans could cause physical injury. Always use care when testing or working with the cooling fans or related equipment.

The electric cooling fans are electrically operated and controlled by two basic electrical circuits. One of the electrical circuits has a temperature sensor which triggers a relay to power the fans. The cooling fan will begin to operate once the coolant temperature reaches the designated temperature of the temperature sensor, which completes the circuit for the fan relay causing the fan to operate.

Possible failures in this circuit include the following:

A failed relay
A failed fan motor
A blown or missing fuse
A defective ignition switch
A defective temperature sensor
Damaged, shorted or disconnected wiring or electrical connector

Possible cooling system problems that could affect the cooling fan operation include:

Coolant leaks
Low coolant level
A restricted radiator
A failed head gasket
A defective water pump
A defective radiator cap
Excessively contaminated coolant

The second electrical circuit that controls the cooling fans is the air conditioner circuit. When the air conditioning is used, the cooling fans automatically operate, regardless of the engine coolant temperature.

This can be a handy tidbit of information to know should the temperature sensor fail. If the air conditioner is turned on, the cooling fans should function if the A/C system is in proper working order.

Possible failures in this circuit include a faulty A/C switch as well as those items from the previous list.

Electric cooling fan circuit failures can be one of several types:

The fans fail to operate, either completely or not within the designed temperature range
The fans run continuously regardless of the coolant temperature with the A/C and ignition switch off
The fans run continuously regardless of the coolant temperature only when the ignition switch is on but with the A/C switch off

The danger of a cooling fan that fails to operate is an overheated engine. A cooling fan that runs all the time only when the ignition is ON never allows the engine to fully warm up and drivability and fuel economy may suffer. A cooling fan that runs all the time even when the ignition is switched OFF , never allows the engine to fully warm up, the drivability and fuel economy may suffer, and the battery will eventually discharge.

To test the cooling fans, proceed as follows:

  1. Detach the electrical connector for the cooling fan. Consult the wiring schematic in Chassis Electrical for the exact wire color for each fan. The black wire is ground and the colored, striped wire is positive.
  3. Carefully connect a 30 amp fused jumper wire between the fan positive wire and the battery positive terminal.
  5. Connect a jumper wire between the fan ground terminal and a known good chassis ground and the fan should operate. If the fan fails to operate, check the test circuit with a known good 12 Volt test light to make sure the jumper leads are functioning properly. If the circuit tests ok and the fan fails to function when connected to the jumper circuit, replace the fan. If the jumper circuit fuse blows, check for a shorted fan wire and test again. If the jumper circuit continues to blow the fuse the fan motor is internally shorted and must be replaced.