DECELERATION G IS UNSTABLE

id300300000500

Outline

Malfunction symptom

Deceleration G is unstable

Description

•  Deceleration G changes during 1 deceleration.

•  When releasing the accelerator pedal under the same conditions, there is a variation in deceleration G.

•  When operating the brake pedal under the same depression force, there is a variation in deceleration G.

Possible cause

Regenerative braking amount is restricted:

•  PCM restricts regenerative braking amount based on signal from drive motor control module

―  Fail-safe due to drive motor control module-related DTC detection

•  PCM restricts regenerative braking amount based on signal from BECM

―  Fail-safe due to BECM-related DTC detection

―  High voltage battery structural part malfunction

―  High voltage battery temperature is high or low

―  High voltage battery is fully charged and high voltage battery cannot accept power generated by regenerative braking (normal operation)

•  The PCM restricts the regenerative braking amount based on the signal from the electronically controlled brake unit. (normal operation)

―  Driving on slippery road

―  Vehicle condition where wheel slip is likely to occur, such as during sudden steering wheel maneuvering

Target regenerative braking amount changes during deceleration:

•  PCM detects drive mode change.

―  Deceleration and acceleration rate switching detected due to operation of steering shift switch (normal operation)

―  Selector lever shifted to N position (normal operation)

―  Accelerator pedal operation detected (normal operation)

System wiring diagram

•  Not applicable

Connector diagram

•  Not applicable

Malfunction symptom	Deceleration G is unstable
Description	• Deceleration G changes during 1 deceleration. • When releasing the accelerator pedal under the same conditions, there is a variation in deceleration G. • When operating the brake pedal under the same depression force, there is a variation in deceleration G.
Possible cause	Regenerative braking amount is restricted: • PCM restricts regenerative braking amount based on signal from drive motor control module ― Fail-safe due to drive motor control module-related DTC detection • PCM restricts regenerative braking amount based on signal from BECM ― Fail-safe due to BECM-related DTC detection ― High voltage battery structural part malfunction ― High voltage battery temperature is high or low ― High voltage battery is fully charged and high voltage battery cannot accept power generated by regenerative braking (normal operation) • The PCM restricts the regenerative braking amount based on the signal from the electronically controlled brake unit. (normal operation) ― Driving on slippery road ― Vehicle condition where wheel slip is likely to occur, such as during sudden steering wheel maneuvering Target regenerative braking amount changes during deceleration: • PCM detects drive mode change. ― Deceleration and acceleration rate switching detected due to operation of steering shift switch (normal operation) ― Selector lever shifted to N position (normal operation) ― Accelerator pedal operation detected (normal operation)
System wiring diagram	• Not applicable
Connector diagram	• Not applicable

Diagnostic Procedure

Step

Inspection

Results

Action

1

VERIFY EV SYSTEM RELATED DTCs

•  Perform the DTC inspections for the following modules.
(See DTC INSPECTION.)

―  PCM

―  BECM

―  Drive motor control module

―  Electronically controlled brake unit

•  Are DTCs displayed?

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

(See DTC TABLE [PCM (e-SKYACTIV)].)

(See DTC TABLE [BECM (e-SKYACTIV)].)

(See DTC TABLE [DRIVE MOTOR CONTROL MODULE (e-SKYACTIV)].)

(See DTC TABLE [ELECTRONICALLY CONTROLLED BRAKE UNIT].)

No

Go to the next step.

2

VERIFY HOW CUSTOMER USES VEHICLE

•  Verify the following driving conditions based on the contents of the interview with the customer.

―  Steering shift switch operation

―  Selector lever shifted to N position

―  Driving on slippery road

―  Vehicle condition where wheel slip is likely to occur, such as during sudden steering wheel maneuvering

―  Accelerator pedal operation detected

•  Does the customer’s driving situation apply?

Yes

Explain to the customer that deceleration G is unstable due to the driving operations during deceleration.

No

Explain to the customer that deceleration G is unstable due to the inhibition of regenerative braking when the vehicle detects the following during deceleration.

•  High voltage battery is fully charged and power generated by regenerative braking cannot be accepted (high voltage battery state of charge (SOC) is 95% or more)

Repair completion verification

VERIFY THAT VEHICLE IS REPAIRED

•  Install/connect the part removed/disconnected during the troubleshooting procedure.

•  Has the malfunction symptom been eliminated?

Yes

Complete the symptom troubleshooting. (Explain contents of repair to customer.)

No

Refer to the CAN (controller area network) malfunction diagnosis flow to inspect for a CAN communication error.

(See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [L.H.D. (E)] .)

(See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [R.H.D.] .)

Step	Inspection	Results	Action
1	VERIFY EV SYSTEM RELATED DTCs • Perform the DTC inspections for the following modules. (See DTC INSPECTION.) ― PCM ― BECM ― Drive motor control module ― Electronically controlled brake unit • Are DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [PCM (e-SKYACTIV)].) (See DTC TABLE [BECM (e-SKYACTIV)].) (See DTC TABLE [DRIVE MOTOR CONTROL MODULE (e-SKYACTIV)].) (See DTC TABLE [ELECTRONICALLY CONTROLLED BRAKE UNIT].)
1		No	Go to the next step.
2	VERIFY HOW CUSTOMER USES VEHICLE • Verify the following driving conditions based on the contents of the interview with the customer. ― Steering shift switch operation ― Selector lever shifted to N position ― Driving on slippery road ― Vehicle condition where wheel slip is likely to occur, such as during sudden steering wheel maneuvering ― Accelerator pedal operation detected • Does the customer’s driving situation apply?	Yes	Explain to the customer that deceleration G is unstable due to the driving operations during deceleration.
2		No	Explain to the customer that deceleration G is unstable due to the inhibition of regenerative braking when the vehicle detects the following during deceleration. • High voltage battery is fully charged and power generated by regenerative braking cannot be accepted (high voltage battery state of charge (SOC) is 95% or more)
Repair completion verification	VERIFY THAT VEHICLE IS REPAIRED • Install/connect the part removed/disconnected during the troubleshooting procedure. • Has the malfunction symptom been eliminated?	Yes	Complete the symptom troubleshooting. (Explain contents of repair to customer.)
Repair completion verification		No	Refer to the CAN (controller area network) malfunction diagnosis flow to inspect for a CAN communication error. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [L.H.D. (E)] .) (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [R.H.D.] .)