HowToRepairGuide.com: how to change heater core 03 accord

Honda Heater Core Replacement

You will have to remove the dashboard to reach the heater core, which is connected to the center console, as well.
Its not very easy task.
But will proper procedure you can do this:

Basic tools like Wrenches,drain pan,screw driver, etc are required.

IMPORTANT NOTE: Before performing any electrical part or connection disassembly,please make sure you disconnect battery negative terminal.Then after 5 minutes you can start your procedure.Because there are few electrical components like Airbag,charging capacitor that still hold charge even after battery is disconnected,so to release there inbuilt charge don't touch any electrical part connections for few minutes after you disconnect the car battery.

ONE MORE IMP NOTE: After disconnecting the battery terminals the system ask for radio code.So
Make sure to acquire the anti-theft code from the radio and write down the frequencies for the radio-s preset buttons.

Heater Core
Removal & Installation procedure
After disconnecting the negative battery cable, wait for at least 3 minutes for the air bag module to deplete its energy before working the on the instrument panel or steering wheel.

Discharge the air conditioning system by disconnecting the suction and the receiver lines from the evaporator core.

Drain the engine coolant.Please use Drain pan to collect the coolant.
From under the hood, open the cable clamp.
Disconnect the heater control cable from the valve.
Turn the valve to the fully opened position.
Disconnect the heater hoses from heater core assembly.
Remove the mounting nut from the heater unit.
Remove the center console as follows.

The procedure for manual transaxle and system equipped with heated system is mentioned:

This includes the gear shift knob (if you have a manual transmission), heat switch connectors (if you have heated seats), front power accessory connector, console mat and rear accessory electrical connector.

If equipped with manual transaxle, remove the shifter knob
Detach the center console retaining clips and pull the assembly upward

If equipped with heated seats, detach the heat switch connectors
Pry up on the right side of the console pocket, detach the clips and remove the pocket

Detach the lower dashboard covers, center pocket assembly and glovebox. Also, take off the driver's side under cover panel for newer models of the Honda Accord.

See below Center Console and its components diagram:
center console diagram

First of all take out the steering column from the dashboard. Then Remove the air bag assembly first and ensure that the column is within the full up position during removal. Hold the slider shaft onto the column with a bit of wire during removal.

FOR STEERING COLUMN REMOVAL PROCEDURE

See below instrument panel bolt locations For Accord

honda accord cluster

Now with the help of helper remove the dashboard assembly. For that first disconnect the center lower covers on both sides, the SRS control unit and all connectors, hoses and harness that will interfere with the dashboard removal.

Now its time to disconnect wire connections and remove the part connected to the wires.Make sure yu note down the wire position and exact location.Disconnect all connectors to the air mix control motor, evaporator temperature sensor, power transistor and recirculation control motor. Remove the wire harness, heater ducts and blower-heater unit. Loosen the heater core cover and remove the heater core.

See below heater housing, evaporator housing and related components diagram for Accord

heater core removal

Mount the new heater core in place. Hook up everything in reverse sequence of removal. Fill up the coolant and test the system at normal running temperatures, verifying for leaks.

Also after complete procedure is done,on some Honda vehicles power window module reprogram is required.Not always but on some cases,so verify if your power windows are functioning right or not.

If not then follow the power window reprogram process:

Reprogram the power window control unit as follows.
Turn the ignition switch ON.
Lower the window, all the way down.
Open the driver-s side door.
Turn the ignition switch OFF.
Push and hold the drivers window DOWN switch.
Turn the ignition switch ON. Release the driver-s window DOWN switch. This must be done within five seconds.
Repeat the above step three more times. Wait one second.

Confirm that the AUTO UP and AUTO DOWN do not work. If they work repeat the procedure, paying close attention to the five second time limit

Move the driver-s window all the way down by holding the drivers window DOWN switch to the AUTO DOWN position.

Pull up and hold the driver-s window UP switch to the AUTO UP position until the window reaches the fully closed position. Hold the switch for one second.

Confirm that the power window master switch has been reset by using the driver-s window AUTO UP and DOWN function.

This will help.
Thanks.

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