I have three units inside my house. Two of them work fine but one of them will not operate and the left operation indicator lamp blinks.

The turn signals are controlled by the BCM
Turn Signal Lamps
The body control module (BCM) is responsible for controlling the turn signals and hazard lamps. When the turn signal switch is placed in either the left turn or right turn position, the BCM receives a signal from the turn signal switch. The BCM then sends an on-off voltage signal to either the left or right turn signals and their instrument panel cluster (IPC) indicator. When the hazard switch is pressed, the BCM receives a signal from the hazard switch. The BCM then will send an on-off voltage signal to all the turn signal lamps. All the turn signal lamps will flash including both IPC turn signal indicators.

I would suspect a problem with the BCM or maybe corrosion in the under hood fuse box . Wires from the BCM to the front turn signals go through the underhood fuse box.
Your best bet ,take it to a qualified repair shop that has a diagnostic scan tool that can read BCM DTC'S - diagnostic trouble codes
DTC B3948 Left Front Turn Signal Circuit
The body control module (BCM) controls the left front turn signal, hazard lamp, and daytime running lamp (DRL). The BCM supplies voltage to control the lighting functions. The BCM monitors the left turn signal lamp supply voltage circuit for proper operation.
DTC B3949 Right Front Turn Signal Circuit

with both lights solid. according to the manual all it says is (there is an electrical failure inside the unit, please take to an authorized servicer). if you are able to do this yourself you will need the schematics and a voltmeter to start testing your voltages. your lamp is fine so dont waste your money replacing that anymore. if you would like the service manual send me an email to [email protected].

Here is what the service manual says. Looks like it is not a flasher relay but a function of the body control module.

TURN SIGNAL AND HAZARD WARNING LAMP SYSTEMSystem Description OUTLINE Turn signal lamp and the hazard warning lamp is controlled by combination switch reading function and the flasher control function of BCM.
TURN SIGNAL LAMP OPERATION - BCM detects the combination switch condition by the combination switch reading function. - BCM supplies voltage to the right (left) turn signal lamp circuit when the ignition switch is turned ON and the turn signal switch is in the right (left) position. BCM blinks the turn signal lamp.
HAZARD WARNING LAMP OPERATION BCM supplies voltage to both turn signal lamp circuit when the hazard switch is turned ON. BCM blinks the hazard warning lamp.
TURN SIGNAL INDICATOR LAMP AND TURN SIGNAL SOUND OPERATION - BCM transmits the turn indicator signal to the combination meter with CAN communication while the turn signal lamp and the hazard warning lamp are operating. - Combination meter outputs the turn signal sound with the integrated buzzer while blinking the turn signal indicator lamp according to the turn indicator signal.
HIGH FLASHER OPERATION (FAIL-SAFE) - BCM detects the turn signal lamp circuit status by the terminal current value. - BCM increases the turn signal lamp blinking speed if the bulb or harness open is detected with the turn signal lamp operating. NOTE: The blinking speed is normal while operating the hazard warning lamp.

AHX18MEV
4 - 12
[8] SELF-DIAGNOSIS FUNCTION
1. Indoor unit
(AH-X18MEV, AH-X18MEV-1, AH-X24MEV, AH-X24MEV-1)
To display the self-diagnosis, hold down the AUX button for over 5 seconds on the indoor unit when the indoor unit is not operating.
• The operation lamp (red), timer lamp (orange) and Super jet lamp lighter) flash to indicate the information of malfunction.
(Display of self-diagnosis result)
The operation lamp (red) and the Super jet lamp (green) flash in synchronization with the timer lamp (orange).
(AH-XP18MV, AH-XP18MV-1, AH-XP24MV, AH-XP24MV-1)
To display the self-diagnosis, hold down the AUX button for over 5 seconds on the indoor unit when the indoor unit is not operating.
• The POWER CONSUMPTION indicator indicates the information of malfunction by showing the main category error (number) and the sub-category
error (-number) alternately in 1-second intervals.
Example: Compressor high-temperature error
Remark

3. CHART
<INDOOR UNIT> ?:1-second ON / 1-second OFF
Problem
symptom
Outdoor
unit indication
(LED1)
Indoor unit Malfunction
No.
Content of diagnosis Check point Action
Lamp Main Sub Main Sub
Normal
condition
Normal
blinking
? ? ? ? ? Timer (Orange) 0 0 Normal
Operation (Red)
Super Jet (Green)
Indoor and
outdoor
units do not
operate.
1-time ? ? ? ? ? Timer (Orange) 1 0 Outdoor unit
thermistor
short-circuit
Heat exchanger
thermistor short
circuit error
(1) Measure the resistance
of the outdoor
unit
thermistors.
(1) Replace the outdoor
unit thermistor
assembly.
? Operation (Red)
Super Jet (Green)
? ? ? ? ? Timer (Orange) 1 Outdoor temperature
thermistor
short circuit error
(2) Check the lead wire
of the outdoor unit
thermistor for torn
sheath and shortcircuit.
(2) Replace the outdoor
unit thermistor
assembly.
? Operation (Red)
? Super Jet (Green)
? ? ? ? ? Timer (Orange) 2 Suction thermistor
short circuit
error
(3) No abnormality
found in above
inspections (1) and
(2).
(3) Replace the outdoor
unit control
PWB assembly.
? Operation (Red)
? Super Jet (Green)
? ? ? ? ? Timer (Orange) 3 2-way valve
thermistor short
circuit error
? Operation (Red)
? ? Super Jet (Green)
LED1
AU-X24MV, AU-X24MEV
AU-X18MV, AU-X18MEV
LED1

Three orange power blinks indicates a 'Malfunction 5', and that your unit requires servicing. You can try pressing POWER on the unit for over 7 seconds, and then turning the set back on after 5 more seconds. If this doesn't help the set needs servicing.

If you didn't reset the lamp timer after replacing it, you might try that by following these steps.

If you think browsing the troubleshooting section of your operating manual may help, you can access it here.

I hope that helps.

poor conection in houseing remove lamp clan conection and make sure its getting a good contact

To reset the lamp operation time on a Mitsbishi XD480U:

Plug in the power cord, turn on the lamp, and press the Left Arrow button, Right Arrow button, and POWER buttons on the control panel ALL AT THE SAME TIME, holding them all down for about three seconds.

Notes:
•Unless these three buttons are pressed at the same time, the lamp operation time isn't reset.
• Make sure that the STATUS indicator is lit twice and the lamp operation time is reset successfully.
• The projector doesn't turn on if the lamp cover isn't attached securely.
• Be sure to reset the lamp operation time whenever you replace the lamp.
• Do not reset the lamp operation time unless you replace the lamp.

To reset the lamp operation time on a Mitsbishi XD480U:

Plug in the power cord, turn on the lamp, and press the Left Arrow button, Right Arrow button, and POWER buttons on the control panel ALL AT THE SAME TIME, holding them all down for about three seconds.

Notes:
•Unless these three buttons are pressed at the same time, the lamp operation time isn't reset.
• Make sure that the STATUS indicator is lit twice and the lamp operation time is reset successfully.
• The projector doesn't turn on if the lamp cover isn't attached securely.
• Be sure to reset the lamp operation time whenever you replace the lamp.
• Do not reset the lamp operation time unless you replace the lamp.

the status light blinking red means a fan (the unit hs 4 of them) has failed. you need to determine which one. use the self diagnostic function:
Error Code Operational Check
Note: The TV must be in “Shut Down” and not manually switched Off, to perform the Error Code Operational
Check. When the TV is switched Off, the code automatically resets to “12” No Error.
Press the front panel “DEVICE” and “MENU” buttons at the same time, and hold for 5 seconds to
activate the Error Code Operational Check. The LED will then flash denoting a two digit Code.
Note: The front panel buttons must be used, NOT those on the Remote Control.
• The number of flashes indicates the value of the MSD (tens digit) of the Error Code.
• The flashing then pauses for approximately 1/2 second.
• The LED then flashes indicating the value of the LSD (ones digit) of the Error Code.
Example: If the Error Code is “32”, the LED will flash three times, pause, and then flash two times.
• The Error Code is repeated a total of 5 times.


and read the code.
35= Chassis Fan failure
36 =Exhaust (Back Cover) or Lamp Ballast Fan failure
37= Engine (DMD or Lamp) Fan failure