DTC P1CCC-96: DC/DC Converter Enable Component Internal Failure [10/2018 - ]: Procedure

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CHECK DTC OUTPUT

Connect the Techstream to the DLC3.
Turn the power switch on (IG).
Enter the following menus: Powertrain / Hybrid Control and Motor Generator / Trouble Codes.

Check for DTCs.

Powertrain > Hybrid Control > Trouble Codes

Powertrain > Motor Generator > Trouble Codes

Result

Result	Proceed to
P1CCC96 only is output, or DTCs except the ones in the table below are also output.	A
DTCs of hybrid control system in the table below are output.	B
DTCs of motor generator control system in the table below are output.	C

TABLE 1

Malfunction Content	System	Relevant DTC
Insulation Malfunction	Hybrid control system	P1C7C49	Hybrid/EV Battery Voltage System Isolation (A/C Area) Internal Electronic Failure
		P1C7D49	Hybrid/EV Battery Voltage System Isolation (Hybrid/EV Battery Area) Internal Electronic Failure
		P1C7E49	Hybrid/EV Battery Voltage System Isolation (Transaxle Area) Internal Electronic Failure
		P1C7F49	Hybrid/EV Battery Voltage System Isolation (Direct Current Area) Internal Electronic Failure
High Voltage Circuit Malfunction	Hybrid control system	P0AA649	Hybrid/EV Battery Voltage System Isolation Internal Electronic Failure
		P0AD911	Hybrid/EV Battery Positive Contactor Circuit Short to Ground
		P0ADD11	Hybrid/EV Battery Negative Contactor Circuit Short to Ground
		P0AE411	Hybrid/EV Battery Precharge Contactor Circuit Short to Ground
		P1C8449	High Voltage Power Resource Circuit Short during Ready ON
		P300449	High Voltage Power Resource Circuit Short during Pre-Charge

TABLE 2

Malfunction Content	System	Relevant DTC
System malfunction	Hybrid control system	P0A9300	Inverter "A" Cooling System
		P0C7396	Motor Electronics Coolant Pump "A" Component Internal Failure
		P314A31	Motor Electronics Coolant Pump "A" No Signal
	Motor generator control system	P0E5717	DC/DC Converter Voltage Sensor "A" (VL) Circuit Voltage Above Threshold

HINT:

P1CCC96 may be output as a result of the malfunction indicated by the DTCs above.

The chart above is listed in inspection order of priority.
Check DTCs that are output at the same time by following the listed order. (The main cause of the malfunction can be determined without performing unnecessary inspections.)

Turn the power switch off.

Result:

GO TO DTC CHART (HYBRID CONTROL SYSTEM). Refer to DIAGNOSTIC TROUBLE CODE CHART [10/2018 - ]

Result:

GO TO DTC CHART (MOTOR GENERATOR CONTROL SYSTEM). Refer to DIAGNOSTIC TROUBLE CODE CHART [10/2018 - ]

Result:

See step 2

CHECK AMD TERMINAL VOLTAGE

WARNING:

Be sure to wear insulated gloves.

Connect the cable to the negative (-) auxiliary battery terminal.

Measure the voltage according to the value(s) in the table below.

Standard Voltage

Tester Connection	Switch Condition	Specified Condition
2D-1 (AMD) - Body ground	Power switch off	Same as auxiliary battery voltage

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

2D-1(AMD)

Disconnect the cable from the negative (-) auxiliary battery terminal.

Result

Proceed to
OK
NG

Result:

See step 7

Result:

See step 3

CHECK AMD TERMINAL CONNECTION CONDITION

WARNING:

Be sure to wear insulated gloves.

Check that the service plug grip is not installed.
NOTE:
After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the appropriate service information because this may cause a malfunction.

Check that the nuts for the AMD terminal are tightened to the specified torque, the AMD terminal is connected securely, and there are no contact problems.

Torque

Inverter with converter assembly side

T=8.0 N*m (82 kgf*cm, 71 in.*lbf)

Engine room R/B No. 1 side

T=8.4 N*m (86 kgf*cm, 74 in.*lbf)

Result

Result		Proceed to
There are no arc marks.	The terminal is connected securely and there are no contact problems.	A
There are no arc marks.	The terminal is not connected securely and there is a contact problem.	B
There are arc marks.	-	C

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*1	AMD Terminal (Inverter with Converter Assembly Side)
*2	AMD Terminal (Engine Room R/B No. 1 Side)

Result:

CONNECT SECURELY

Result:

REPLACE MALFUNCTIONING PARTS

Result:

See step 4

CHECK ENGINE WIRE

WARNING:

Be sure to wear insulated gloves.

Check that the service plug grip is not installed.
NOTE:
After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the appropriate service information because this may cause a malfunction.
Disconnect the engine wire from the AMD terminal (inverter with converter assembly side and engine room R/B No. 1 side).

Measure the resistance according to the value(s) in the table below.

Standard Resistance

Tester Connection	Condition	Specified Condition
C45-1 (AMD) - 2D-1 (AMD)	Always	Below 1 Ω

Install the engine wire.

Result

Proceed to
OK
NG

Result:

REPLACE ENGINE WIRE

Result:

See step 5

CHECK COOLING SYSTEM
Refer to Cooling System [10/2018 - ]

Result

Proceed to

NEXT

Result:

NEXT

See step 6

Proceed to
NEXT

CHECK DC/DC CONVERTER FUNCTION

HINT:

The current at the AMD terminal cannot be measured directly because of space limitations. Measure the current flowing at the auxiliary battery instead.

Connect the AC/DC 400 A probe of the tester to the positive (+) auxiliary battery cable.
Install the service plug grip.
Connect the cable to the negative (-) auxiliary battery terminal.
Turn the power switch on (READY) and leave the vehicle as it is until the electric current flowing to the auxiliary battery becomes 10 A or less.
HINT:

If the power switch turns off immediately after it is turned on (READY), auxiliary battery voltage may be low. Recharge the auxiliary battery and perform this procedure again.

Measure the current flowing from the auxiliary battery with the power switch on (READY), the headlight position switch and blower motor switch in the HI position, and the rear window defogger turned on.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	Probe Direction
*b	Current Flowing to Auxiliary Battery

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	Probe Direction
*b	Current Flowing from Auxiliary Battery

Standard Current

Item	Condition	Specified Condition
Current flowing from auxiliary battery	Power switch on (READY) (The headlight position switch and blower motor switch are in the HI position, and the rear window defogger is turned on.)	0 A or less (no current from auxiliary battery)

Measure the voltage according to the value(s) in the table below.

Standard Voltage

Item	Condition	Specified Condition
Auxiliary battery voltage	Power switch on (READY) (The headlight position switch and blower motor switch are in the HI position, and the rear window defogger is turned on.)	12.5 to 15 V

Turn the power switch off.

Result

Proceed to
OK
NG

Result:

REFER TO REPLACE INVERTER WITH CONVERTER ASSEMBLY PARTS. Refer to DTC CHECK / CLEAR [10/2018 - ]

Result:

See step 8

CHECK FUSE (DC/DC)

Disconnect the cable from the negative (-) auxiliary battery terminal.

Remove the DC/DC fuse from No. 1 engine room relay block.

*1	No. 1 Engine Room Relay Block
*2	DC/DC fuse

Measure the resistance according to the value(s) in the table below.

Standard Resistance

Tester Connection	Condition	Specified Condition
DC/DC fuse	Always	Below 1 Ω

Result

Proceed to
OK
NG

Result:

REPAIR OR REPLACE WIRE HARNESS

Result:

REPLACE FUSE (DC/DC)

CHECK HIGH VOLTAGE INSULATION

WARNING:

Be sure to wear insulated gloves.

Check that the service plug grip is not installed.
NOTE:
After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the appropriate service information because this may cause a malfunction.
Remove the inverter cover from the inverter with converter assembly.

Using a megohmmeter set to 500 V, measure the insulation resistance according to the value(s) in the table below.

NOTE:

Be sure to set the megohmmeter to 500 V when performing this test. Using a setting higher than 500 V can result in damage to the component being inspected.

Standard Resistance

Tester Connection	Switch Condition	Specified Condition
v2-1 (W) - Body ground and shield ground	Power switch off	1 MΩ or higher
v2-2 (U) - Body ground and shield ground	Power switch off	1 MΩ or higher
v2-3 (V) - Body ground and shield ground	Power switch off	1 MΩ or higher
v2-4 (W) - Body ground and shield ground	Power switch off	1 MΩ or higher
v2-5 (U) - Body ground and shield ground	Power switch off	1 MΩ or higher
v2-6 (V) - Body ground and shield ground	Power switch off	1 MΩ or higher

HINT:

Perform this inspection while the motor cable are connected.

Install the inverter cover to the inverter with converter assembly.

Result

Proceed to
OK
NG

Result:

REFER TO REPLACE INVERTER WITH CONVERTER ASSEMBLY PARTS. Refer to DTC CHECK / CLEAR [10/2018 - ]

Result:

See step 9

CHECK GENERATOR HIGH-VOLTAGE CIRCUIT
Refer to Generator High-voltage Circuit [10/2018 - ]

Result

Proceed to

NEXT

Result:

NEXT

See step 10
CHECK MOTOR HIGH-VOLTAGE CIRCUIT
Refer to Motor High-voltage Circuit [10/2018 - ]

HINT:

If the "Motor High-voltage Circuit" inspection results are normal, perform the next step.

Result

Proceed to

NEXT

Result:

NEXT

REFER TO REPLACE INVERTER WITH CONVERTER ASSEMBLY PARTS. Refer to DTC CHECK / CLEAR [10/2018 - ]