[Previous][Next]
DTC B102A: BATT.cooling air thermo SNS.low
DTC B102B: BATT.cooling air thermo SNS.high
 
 
 
 
DTC SET CONDITION
These codes are set when short to ground (DTC B102A) or open circuit (DTC B102B) is detected in the main drive lithium-ion battery fin thermo sensor circuit.
 
 
TROUBLESHOOTING HINTS
  • Defective evaporator (in the main drive lithium-ion battery)
  • The wiring harness or connectors may have loose, corroded, or damaged terminals, or terminals pushed back in the connector
  • Malfunction of heater controller assembly (A/C-ECU)
 
 
DIAGNOSIS
Required Special Tools:
  • MB991223: Harness Set
  • MB992006: Extra Fine Probe
STEP 1. Resistance measurement at heater controller assembly (A/C-ECU) connector.
(1) Remove the heater controller assembly (A/C-ECU) connector, and measure at the wiring harness side.
(2) Resistance between heater controller assembly (A/C-ECU) connector terminal RRAT and SENG.
OK: 11.0 - 11.7 Ω
Is the check result normal?
Go to Step 6.
Go to Step 2.
 
STEP 2. Resistance measurement at main drive lithium-ion battery connector.
(1) Remove the main drive lithium-ion battery connector, and measure at the main drive lithium-ion battery side.
(2) Resistance between main drive lithium-ion battery connector terminal RRAT line and SENG line.
OK: 11.0 - 11.7 Ω
Is the check result normal?
Go to Step 3.
Go to Step 5.
 
STEP 3. Check of open and short circuit in RRAT - line between the main drive lithium-ion battery fin thermo sensor (in the evaporator) and the heater controller assembly (A/C-ECU) connector.
Is the check result normal?
Go to Step 4.
Repair the connector(s) or wiring harness.
 
STEP 4. Check of open and short circuit in SENG line between the main drive lithium-ion battery fin thermo sensor (in the evaporator) and the heater controller assembly (A/C-ECU) connector.
Is the check result normal?
Intermittent malfunction. Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points, - How to Cope with Intermittent Malfunctions ).
Repair the connector(s) or wiring harness.
 
STEP 5. Resistance measurement at main drive lithium-ion battery fin thermo sensor (in the evaporator) connector.
(1) Remove the battery tray cover (Refer to GROUP 54Dc - Main Drive Lithium-ion Battery ).
(2) Remove the main drive lithium-ion battery fin thermo sensor (in the evaporator) connector, and resistance between terminals.
OK: 11.0 - 11.7 Ω
Is the check result normal?
Repair the connector(s) or wiring harness.
Replace the evaporator (Refer to GROUP 54Dc - Main Drive Lithium-ion Battery ).
 
STEP 6. Using scan tool (M.U.T.-IIISE), check whether the DTC is set again.
(1)
cautionTo prevent damage to scan tool (M.U.T.-IIISE), always turn the electric motor switch to the OFF position before connecting or disconnecting scan tool (M.U.T.-IIISE).
Connect scan tool (M.U.T.-IIISE). Refer to "How to connect the Scan Tool (M.U.T.-IIISE) ".
(2) Turn the electric motor switch from OFF position to ON position.
(3) Check the DTC.
(4) Turn the electric motor switch to the OFF position.
Is the DTC set?
Replace the heater controller assembly (A/C-ECU) (Refer to ).
Intermittent malfunction. Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points, - How to Cope with Intermittent Malfunctions ).