2003 Honda CRV Door chime to say headlights are on stopped

Hi JohnnyBMe,

The door and dome light switch are the same for iindicating when the door is open. The dome light has an additional switch that can operate to over ride the door switch.

If the dome light is working with the doors being opened, then the door switch is not the cause of the peoblem.

The other likely cause would be the key in switch. It is located on the key cylinder and not operating to inform the system that the ignition key has been turned off.

Another possibility is a faulty integrated control relay plugged into the under dash fuse box.

Sorry for a mistake made in my earlier reply. The integrated control relay is for an older version and for your model it is known as Multiplex Control Syatem.

All the problem listed falls under this control system.

Here is a description of the system.

MULTIPLEX CONTROL SYSTEM

SYSTEM DESCRIPTIONS
The multiplex control system has four internal functions:
"Â Multiplexing (send multiple signals over shared wires)
"Â Wake up/sleep (runs at full power only on demand to reduce battery draw)
"Â Fail-safe (fixes or ignores faulty signals)
"Â Self-diagnosis (Mode 1 for system DTCs, Mode 2 for input lines)

The system controls the function of these circuits:
"Â Entry light control (ignition key light and ceiling light)
"Â Wiper/washer (intermittent wipe and park functions)
"Â Interlock system
"Â Keyless/power door lock
"Â Gauge assembly, temperature gauge, and indicator lights
"Â HVAC (Compressor and fan control)
"Â Key-in reminder
"Â Lights-on reminder
"Â Seat belt reminder

MULTIPLEX COMMUNICATION

To reduce the number of wire harnesses, digital signals are sent via shared multiplex communication lines rather than sending normal electrical signals through individual wires.

"Â The input signals from each switch are converted to digital signals at the central processing unit (CPU).
"Â The digital signals are sent from the transmitting unit to the receiving unit as serial signals.
"Â The transmitted signal is converted to a switch signal at the receiving unit, and it operates the related component or monitors a switch.
"Â There are exclusive communication lines between the ECM/PCM, the gauge assembly, the keyless receiver unit, and the under-dash fuse/relay box.

WAKE-UP AND SLEEP

The multiplex control system has "wake-up" and "sleep" functions to decrease parasitic draw on the battery when the ignition switch is OFF.

"Â In the sleep mode, the multiplex control unit stops functioning (communication and CPU control) when it is not necessary for the system to operate.
"Â As soon as any operation is requested (for example, a door is unlocked), the related control unit in the sleep mode immediately wakes up and begins to function.
"Â When the ignition switch is turned OFF, and the driver's or front passenger's door is opened, then closed, there is about a 40 second delay before the control unit goes from the wake-up mode to the sleep mode.
"Â If any door is open, the sleep mode will not function.
"Â If a key is in the ignition switch, the sleep mode will not function.
"Â When in sleep mode, the draw is reduced from 70-80 mA to less than 10 mA.

FAIL-SAFE

To prevent improper operation, the multiplex control system has a fail-safe function. In the fail-safe mode, the output signal is fixed when any part of the system malfunctions (for example, a faulty control unit or communication line).

Each control unit has a hardware fail-safe function that fixes the output signal when there is any CPU malfunction, and a software fail-safe function that ignores the signal from the malfunctioning control unit and allows the system to operate normally.

Check the # 9 fuse in underdash fuse box. Replace it if it is blown.

Diagnostics can be done with the aid of a special tools which can be fabricated, it is a jumper wire as shown in diagram.

Get the jumper ready and I will send you the diagnostic procedures.

Yes, a faulty door switch would cause the problem.

I am not sure which tyoe of switch is used for your vehicle but for most Honda door switches, push the moveable tab and you would notice a crossed head screw.

Remove the screw and the switch can be pulled out, it is slotted in, behind which you would see a wire coupler. Disconnect the coper and the switch can be replaced.

You are welcomed.

Yes, it is rather simple. The rubber cover can be removed by pulling at the edges and you would see the holding screw after removal.

You are welcomed and it must have been your lucky day.

Thanks for the input.