B1498

AIR CONDITIONING SYSTEM: B1498/98: Communication Malfunction (A/C Inverter Local)

DTC B1498/98 - Communication Malfunction (A/C Inverter Local)

DESCRIPTION

The hybrid vehicle control ECU and w/ motor compressor transmit information to one another via communication line. Compressor control is stopped and the DTC is output if communication information is cut off or abnormal information occurs.
The DTC is also detected if high-voltage power supplied from the w/ converter inverter assembly to the compressor control circuit is shut off.
The output DTC is memorized as previous trouble.
CAUTION:
- Wear electrically insulated gloves and pull out the service plug grip before inspection as procedures may require disconnecting high-voltage connectors. Be sure to carry the removed service plug grip because other workers may install it by mistake.
- Do not touch the high-voltage connectors or terminals for 5 minutes after the service plug grip is removed.





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK DIAGNOSTIC TROUBLE CODE
(a) Check if DTCs for the hybrid control system are output using the Techstream.
Result:






B -- GO TO HYBRID CONTROL SYSTEM
A -- Continue to next step.
2. INSPECT HEATER FUSE
(a) Remove the HEATER fuse from instrument panel J/B.
(b) Measure the resistance according to the value(s) in the table below.
Resistance:






NG -- REPLACE HEATER FUSE
OK -- Continue to next step.
3. CHECK HARNESS AND CONNECTOR (W/MOTOR COMPRESSOR ASSEMBLY - BODY GROUND)





(a) Disconnect the connector from w/ motor compressor assembly.
CAUTION: Do not disconnect the connector on the high-voltage side.
(b) Measure the resistance according to the value(s) in the table below.
Resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
4. CHECK HARNESS AND CONNECTOR (IG - GND)





(a) Turn the ignition switch ON.
(b) Measure the voltage according to the value(s) in the table below.
Voltage:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
5. CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - W/MOTOR COMPRESSOR ASSEMBLY)





(a) Disconnect the connector from the hybrid vehicle control ECU.
(b) Measure the resistance according to the value(s) in the table below.
Resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
6. INSPECT ELECTRIC VEHICLE FUSE
(a) Turn the ignition switch off.
(b) Remove the service plug grip.
CAUTION:
- Be sure to wear insulated gloves.
- Do not touch the high-voltage connectors or terminals for 5 minutes after the service plug grip is removed.
NOTE: Do not start the engine with the service plug grip removed because it may cause a malfunction.
(c) Remove the inverter cover.
NOTICE:
- Tape the interlock round terminal for the inverter cover to prevent it from being grounded.
- Be sure to prevent foreign objects or water from entering the w/ converter inverter assembly.





(d) Check that the A and B bolts are tightened securely.
(e) Measure the resistance according to the value(s) in the table below.
Resistance:






NG -- REPLACE ELECTRIC VEHICLE FUSE
OK -- Continue to next step.
7. INSPECT W/CONVERTER INVERTER ASSEMBLY
CAUTION:
- Be sure to wear insulated gloves.
- Be sure to prevent foreign objects or water from entering the w/ converter inverter assembly.
(a) Check that the 1 and 2 bolts are tightened securely.
Torque: 8.0 Nm (82 kgf-cm, 71 in-lbf)





(b) Disconnect the connector from the air conditioning wiring harness sub-assembly.
(c) Measure the resistance according to the value(s) in the table below.
Resistance:






NG -- REPLACE W/CONVERTER INVERTER ASSEMBLY
OK -- Continue to next step.
8. INSPECT ENGINE WIRE NO.4





(a) Disconnect the connector from the engine wire No.4.
(b) Measure the resistance according to the value(s) in the table below.
Resistance:






NG -- REPAIR OR REPLACE ENGINE WIRE NO.4
OK -- Continue to next step.
9. INSPECT W/MOTOR COMPRESSOR ASSEMBLY





(a) Reconnect the connectors to the engine wire No.4, air conditioner harness, hybrid vehicle control ECU and w/ motor compressor assembly.
(b) Turn the ignition switch ON.
(c) Measure the waveform according to the condition in the illustration.





(1) CLK - Body ground
OK:
Waveform appears.
HINT: Waveform cycle varies with the communication contents.





(2) ITE - Body ground
OK:
Waveform appears.
HINT: Waveform cycle varies with the communication contents.

NG -- REPLACE W/MOTOR COMPRESSOR ASSEMBLY
OK -- REPLACE HYBRID VEHICLE CONTROL ECU