OBD Code B2426: Passenger Solar Radiation Sensor Circuit Open

Q: What does OBD code B2426 mean?

Passenger Solar Radiation Sensor Circuit Open. The passenger-side solar radiation sensor has a broken electrical connection, like a cut wire in a lamp preventing current flow. The climate control system can't detect how much sun is hitting that side of the vehicle.

Q: How do I fix OBD fault code B2426?

Inspect and reseat the sensor connector on the passenger dashboard or A-pillar for corrosion or loose pins.. Check the wiring between sensor and climate control module for pinched, frayed, or corroded sections.. Replace the sensor unit if connector and wiring are intact and no voltage is present at the harness.

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What This Actually Means

In plain language — no jargon

The passenger-side solar radiation sensor has a broken electrical connection, like a cut wire in a lamp preventing current flow. The climate control system can't detect how much sun is hitting that side of the vehicle.

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Symptoms You May Notice

3 known symptoms for this code

Climate control not adjusting passenger side temperature properly

Uneven cabin temperature between driver and passenger sides

Reduced automatic climate efficiency on sunny days

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How Your ECU Detects This

Technical sensor logic and voltage thresholds

The ECU monitors voltage input from the solar radiation sensor to measure infrared energy hitting the passenger window. It uses this data to adjust HVAC blend doors and fan speed for optimal comfort. An open circuit prevents voltage signals from reaching the ECU.

Voltage & Parameter Thresholds

Parameter	Normal Range	Fault Condition
Sensor voltage	0.5–4.5V proportional to solar load	No voltage signal or stuck at 0V/5V
Circuit resistance	<50Ω	Infinite resistance (open circuit)

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Diagnostic & DIY Fix Guide

Check these in order — from cheapest to most complex

1

Wiring harness connector

Inspect and reseat the sensor connector on the passenger dashboard or A-pillar for corrosion or loose pins.

2

Wiring and splice points

Check the wiring between sensor and climate control module for pinched, frayed, or corroded sections.

3

Solar radiation sensor

Replace the sensor unit if connector and wiring are intact and no voltage is present at the harness.

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When to See a Professional Mechanic

Not all fault codes are safe to DIY

Code B2426 is a low-severity fault. Your vehicle is generally safe to drive to a workshop for diagnosis. However, do not ignore it indefinitely — low-severity codes often indicate developing problems that become expensive if neglected. Book a diagnostic appointment within 2–4 weeks. If you notice any additional symptoms (rough running, power loss, unusual smells), treat it as higher priority.

Safety note: OBD-II codes identify the system or circuit where a fault was detected — they do not always identify the exact failed component. A professional mechanic using live sensor data will diagnose the root cause more accurately than replacing parts based on the code alone.

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How to Clear Code B2426

What happens after you fix the fault

Once the fault is repaired, B2426 can be cleared using any OBD-II scanner. Connect the scanner, navigate to "Clear Codes" or "Erase DTCs," and confirm. The check engine light turns off immediately.

The code will return if the root cause was not actually fixed. The ECM re-detects the fault within 1–3 drive cycles and sets the code again.

✅ Safe to Clear When

Fault has been diagnosed and repaired
You want to confirm the repair worked
Code appeared after a sensor was cleaned

⚠️ Do Not Clear When

Preparing for an emissions/PUC test
Root cause is still undiagnosed
Check engine light is flashing

Emissions test note: Clearing codes resets OBD readiness monitors. Most vehicles need 50–100 km of mixed driving before monitors complete. Do not clear codes immediately before an emissions or PUC inspection.