Code No. B1001:
Interior temperature sensor Low
Code No. B1002:
Interior temperature sensor High
DIAGNOSIS CODE SET CONDITIONS
These codes are set when abnormality of the room temperature sensor integrated in A/C-ECU is detected.
PROBABLE CAUSES
- Malfunction of interior temperature sensor
- Damaged harness wires and connectors
- Malfunction of the A/C-ECU
DIAGNOSIS PROCEDURE
STEP 1. M.U.T.-III data list
Check that the following service data display contents are normal.
- Item 21:
Interior temperature sensor
Q.
Is the check result normal?
Go to Step 2.
Replace the A/C-ECU.
STEP 2. Check whether the diagnosis code is reset.
Q.
Is the diagnosis code set?
Replace the A/C-ECU.
Intermittent malfunction. Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points, - How to Cope with Intermittent Malfunctions 
.)
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