DTC P0646:00 [PCM (SKYACTIV-D 2.2)]

id0102j5587900


Engine Type

Item

Reference
Fuel injector (2 pin type)
(See Fuel injector (2 pin type).)
Fuel injector (6 pin type)
(See Fuel injector (6 pin type).)


Fuel injector (2 pin type)

DTC P0646:00

A/C relay circuit low input
DETECTION CONDITION
•  When all of the following conditions are met, a condition whereby the A/C relay control circuit voltage is less than the specification continues for 5 s.
―  Battery positive voltage: 8—20 V
―  0.5 s have elapsed after ignition is switched ON (engine off or on)
―  During A/C relay off control
Diagnostic support note
•  This is a continuous monitor (other).
•  The check engine light does not illuminate.
•  FREEZE FRAME DATA/Snapshot data is available.
•  DTC is stored in the PCM memory.
FAIL-SAFE FUNCTION
•  Stops the G-vectoring control (GVC).
•  Limits the engine transaxle total control.
•  Inhibits the A/C control.
POSSIBLE CAUSE
•  Front body control module (FBCM) detects DTC
•  A/C relay malfunction
•  Front body control module (FBCM) connector or terminal malfunction
•  Short to ground in wiring harness between the following terminals:
―  Front body control module (FBCM) terminal 1C and A/C relay terminal A
―  A/C relay terminal E and PCM terminal 2BE
•  PCM connector or terminal malfunction
•  Front body control module (FBCM) malfunction
•  PCM malfunction

Diagnostic Procedure

Step

Inspection

Results

Action
1
RECORD VEHICLE STATUS WHEN DTC WAS DETECTED TO UTILIZE WITH REPEATABILITY VERIFICATION
Note
•  Recording can be facilitated using the screen capture function of the PC.
•  Record the freeze frame data/snap shot data.
—
Go to the next step.
2
VERIFY FRONT BODY CONTROL MODULE (FBCM) DTCs
•  Perform the DTC inspection for the front body control module (FBCM) using the M-MDS.
•  Is a DTC displayed?
Yes
Repair the malfunctioning location according to the applicable DTC troubleshooting.
(See DTC TABLE [PCM (SKYACTIV-D 2.2)].)
No
Go to the next step.
3
INSPECT A/C RELAY FOR MALFUNCTION
•  Switch the ignition OFF.
•  Remove the A/C relay.
•  Inspect the A/C relay.
•  Is the A/C relay normal?
Yes
Go to the next step.
No
Replace the A/C relay, then go to Step 8.
4
INSPECT FRONT BODY CONTROL MODULE (FBCM) CONNECTOR CONDITION
•  Disconnect the front body control module (FBCM) connector.
•  Inspect the connector engagement and connection condition, and inspect the terminals for damage, deformation, corrosion, or disconnection.
•  Is the connector normal?
Yes
Go to the next step.
No
Repair or replace the connector, then go to Step 8.
5
INSPECT PCM CONNECTOR CONDITION
•  Disconnect the PCM connector.
•  Inspect the connector engagement and connection condition, and inspect the terminals for damage, deformation, corrosion, or disconnection.
•  Is the connector normal?
Yes
Go to the next step.
No
Repair or replace the connector, then go to Step 8.
6
INSPECT A/C RELAY CIRCUIT FOR SHORT TO GROUND
•  Verify that the A/C relay has been removed.
•  Verify that the front body control module (FBCM) connector is disconnected.
•  Inspect for continuity between the following terminals (vehicle wiring harness side) and ground.
―  A/C relay terminal A
―  A/C relay terminal E
•  Is there continuity?
Yes
•  Refer to the wiring diagram and verify if there is a common connector between the following terminals.
―  Front body control module (FBCM) terminal 1C and A/C relay terminal A
―  A/C relay terminal E and PCM terminal 2BE
If there is a common connector:
―  Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for short to ground to determine the malfunctioning location.
―  Repair or replace the malfunctioning location.
If there is no common connector:
―  Repair or replace the wiring harness which is shorted to ground.
Go to Step 8.
No
Go to the next step.
7
INSPECT FRONT BODY CONTROL MODULE (FBCM)
•  Inspect front body control module (FBCM).
•  Is the front body control module (FBCM) normal?
Yes
Go to the next step.
No
Replace the front body control module (FBCM), then go to the next step.
(See FRONT BODY CONTROL MODULE (FBCM) REMOVAL/INSTALLATION.)
8
VERIFY THAT REPAIRS HAVE BEEN COMPLETED
•  Reconnect all the disconnected connectors.
•  Refer to the [MEMORY CLEARING PROCEDURE] and clear the DTC.
•  Start the engine.
•  Switch the A/C between ON/OFF.
•  Display the DTCs using the M-MDS.
•  Has DTC P0646:00 been recorded?
Yes
Repeat the inspection from Step 1.
•  If the malfunction recurs, replace the PCM, then go to the next step.
No
Go to the next step.
9
VERIFY OTHER DTCs
•  Has any other DTC or pending code been stored?
Yes
Repair the malfunctioning location according to the applicable DTC troubleshooting.
(See DTC TABLE [PCM (SKYACTIV-D 2.2)].)
No
DTC troubleshooting completed.


Fuel injector (6 pin type)

DTC P0646:00

A/C relay circuit low input
DETECTION CONDITION
•  When all of the following conditions are met, a condition whereby the A/C relay control circuit voltage is less than the specification continues for 5 s.
―  Battery positive voltage: 8—16 V
―  0.5 s have elapsed after ignition is switched ON (engine off or on)
―  During A/C relay off control
Diagnostic support note
•  This is a continuous monitor (other).
•  The check engine light does not illuminate.
•  FREEZE FRAME DATA/Snapshot data is available.
•  DTC is stored in the PCM memory.
FAIL-SAFE FUNCTION
•  Stops the G-vectoring control (GVC).
•  Limits the engine transaxle total control.
•  Inhibits the A/C control.
POSSIBLE CAUSE
•  Front body control module (FBCM) detects DTC
•  A/C relay malfunction
•  Front body control module (FBCM) connector or terminal malfunction
•  Short to ground in wiring harness between the following terminals:
―  Front body control module (FBCM) terminal 1C and A/C relay terminal A
―  A/C relay terminal E and PCM terminal 2BA
•  PCM connector or terminal malfunction
•  Front body control module (FBCM) malfunction
•  PCM malfunction

Diagnostic Procedure

Step

Inspection

Results

Action
1
RECORD VEHICLE STATUS WHEN DTC WAS DETECTED TO UTILIZE WITH REPEATABILITY VERIFICATION
Note
•  Recording can be facilitated using the screen capture function of the PC.
•  Record the freeze frame data/snap shot data.
—
Go to the next step.
2
VERIFY FRONT BODY CONTROL MODULE (FBCM) DTCs
•  Perform the DTC inspection for the front body control module (FBCM) using the M-MDS.
•  Is a DTC displayed?
Yes
Repair the malfunctioning location according to the applicable DTC troubleshooting.
(See DTC TABLE [PCM (SKYACTIV-D 2.2)].)
No
Go to the next step.
3
INSPECT A/C RELAY FOR MALFUNCTION
•  Switch the ignition OFF.
•  Remove the A/C relay.
•  Inspect the A/C relay.
•  Is the A/C relay normal?
Yes
Go to the next step.
No
Replace the A/C relay, then go to Step 8.
4
INSPECT FRONT BODY CONTROL MODULE (FBCM) CONNECTOR CONDITION
•  Disconnect the front body control module (FBCM) connector.
•  Inspect the connector engagement and connection condition, and inspect the terminals for damage, deformation, corrosion, or disconnection.
•  Is the connector normal?
Yes
Go to the next step.
No
Repair or replace the connector, then go to Step 8.
5
INSPECT PCM CONNECTOR CONDITION
•  Disconnect the PCM connector.
•  Inspect the connector engagement and connection condition, and inspect the terminals for damage, deformation, corrosion, or disconnection.
•  Is the connector normal?
Yes
Go to the next step.
No
Repair or replace the connector, then go to Step 8.
6
INSPECT A/C RELAY CIRCUIT FOR SHORT TO GROUND
•  Verify that the A/C relay has been removed.
•  Verify that the front body control module (FBCM) connector is disconnected.
•  Inspect for continuity between the following terminals (vehicle wiring harness side) and ground.
―  A/C relay terminal A
―  A/C relay terminal E
•  Is there continuity?
Yes
•  Refer to the wiring diagram and verify if there is a common connector between the following terminals.
―  Front body control module (FBCM) terminal 1C and A/C relay terminal A
―  A/C relay terminal E and PCM terminal 2BA
If there is a common connector:
―  Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for short to ground to determine the malfunctioning location.
―  Repair or replace the malfunctioning location.
If there is no common connector:
―  Repair or replace the wiring harness which is shorted to ground.
Go to Step 8.
No
Go to the next step.
7
INSPECT FRONT BODY CONTROL MODULE (FBCM)
•  Inspect front body control module (FBCM).
•  Is the front body control module (FBCM) normal?
Yes
Go to the next step.
No
Replace the front body control module (FBCM), then go to the next step.
(See FRONT BODY CONTROL MODULE (FBCM) REMOVAL/INSTALLATION.)
8
VERIFY THAT REPAIRS HAVE BEEN COMPLETED
•  Reconnect all the disconnected connectors.
•  Refer to the [MEMORY CLEARING PROCEDURE] and clear the DTC.
•  Start the engine.
•  Switch the A/C between ON/OFF.
•  Display the DTCs using the M-MDS.
•  Has DTC P0646:00 been recorded?
Yes
Repeat the inspection from Step 1.
•  If the malfunction recurs, replace the PCM, then go to the next step.
No
Go to the next step.
9
VERIFY OTHER DTCs
•  Has any other DTC or pending code been stored?
Yes
Repair the malfunctioning location according to the applicable DTC troubleshooting.
(See DTC TABLE [PCM (SKYACTIV-D 2.2)].)
No
DTC troubleshooting completed.