DTC B1421/21 Solar Sensor Circuit (Passenger Side) |

| DTC No. | DTC Detection Condition | Trouble Area |
| B1421/21 | Open or short in passenger side solar sensor circuit |
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| 1.READ VALUE OF INTELLIGENT TESTER |
Connect the intelligent tester to the DLC3.
Turn the engine switch on (IG) and push the intelligent tester main switch on.
Select the item below in the Data List, and read the display on the intelligent tester.
| Item | Measure Item / Display (Range) | Normal Condition | Diagnostic Note |
| Solar Sensor (P side) (Solar Sens - P) | Passenger side solar sensor / Min.: 0, Max.: 255 | Passenger side solar sensor voltage increases as brightness increases | - |
| NG | A |
| OK (Checking from the PROBLEM SYMPTOMS TABLE) | B |
| OK (Checking from the DTC) | C |
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| A | |
| 2.INSPECT MULTIPLEX NETWORK BODY ECU |
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Remove the cowl side junction block RH with its connectors still connected.
Measure the resistance of the multiplex network body ECU.
| Tester Connection | Condition | Specified Condition |
| 4 (CLTE) - Body ground | Always | Below 1 Ω |
Measure the voltage of the multiplex network body ECU.
| Tester Connection | Condition | Specified Condition |
| 6 (CLTB) - 4 (CLTE) | Engine switch on (IG) | 10 to 14 V |
| Engine switch off | Below 1 V |
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| OK | |
| 3.CHECK WIRE HARNESS (SOLAR SENSOR - MULTIPLEX NETWORK BODY ECU) |
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Disconnect the M1 solar sensor connector.
Measure the resistance of the wire harness side connectors.
| Tester Connection | Condition | Specified Condition |
| M1-3 (CLTE) - Body ground | Always | Below 1 Ω |
| M1-6 (CLTB) - M1-3 (CLTE) | Engine switch off | Below 1 Ω |
Measure the voltage of the wire harness side connectors.
| Tester Connection | Condition | Specified Condition |
| M1-6 (CLTB) - M1-3 (CLTE) | Engine switch on (IG) | 10 to 14 V |
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| OK | |
| 4.CHECK WIRE HARNESS (SOLAR SENSOR - A/C AMPLIFIER) |
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Disconnect the M1 solar sensor connector.
Disconnect the L52 A/C amplifier connector.
Measure the resistance of the wire harness side connectors.
| Tester Connection | Condition | Specified Condition |
| L52-14 (TSP) - M1-1(TSL) *2 | Always | Below 1 Ω |
| L52-14 (TSP) - M1-2 (TSR) *1 | Always | Below 1 Ω |
| L52-14 (TSP) - Body ground | Always | 10 kΩ or higher |
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| OK | |
| 5.CHECK SOLAR SENSOR |
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Remove the solar sensor with its connector still connected.
Apply battery voltage between terminals 6 (CLTB) and 3 (CLTE) of the solar sensor.
Measure the voltage of the sensor.
| Tester Connection | Condition | Specified Condition |
| 1 (TSL) *2 - 3 (CLTE) | Sensor is subjected to electric light | 0.8 to 4.3 V |
| 2 (TSR) *1 - 3 (CLTE) | Sensor is subjected to electric light | 0.8 to 4.3 V |
| 1 (TSL) *2 - 3 (CLTE) | Sensor is covered with a cloth | Below 0.8 V |
| 2 (TSR) *1 - 3 (CLTE) | Sensor is covered with a cloth | Below 0.8 V |
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| OK | ||
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