B1066 is a short to power, not an open. The Nissan airbag module has found the passenger airbag circuit connected to a voltage source it should never touch, and it disables the system in response.
Squib circuits are supposed to be isolated, with the module controlling both sides of the loop. When one of those conductors makes contact with a powered wire, the module sees voltage where it should see only its own test current. B1066 is the entry for that condition on the passenger airbag circuit, and it is treated seriously because an unintended power path near a firing circuit is exactly what the isolation exists to prevent.
Shorts to power usually come from damaged insulation in a bundle where the airbag wiring runs alongside powered circuits, or from aftermarket work that tapped into the wrong harness. Behind the dash, the SRS harness shares space with radio power, lighting, and accessory feeds, so a pinch or a bad splice puts the two in contact.
The module measures this condition live, so B1066 belongs with the circuit codes and it clears once the unintended power path is gone. Crash data is stored differently. It goes into memory at the moment a bag fires, stays there permanently, and no scan tool clear or wiring repair removes it without a module reset.
A short to power is a wiring condition and a reset does not address it. The code returns the moment the module powers up and measures again. Find the contact point, repair it, and confirm the circuit is isolated. Our mail in reset is the right service for Nissan modules holding crash data after a deployment, once the vehicle repairs are finished.
Nissan is the make listed for B1066. If the vehicle has had aftermarket electronics installed at any point, that history is worth knowing up front, since improvised power taps behind the dash are a frequent source of this exact code.
Disconnect the passenger airbag and check for voltage on the harness side with the key on, because finding voltage there proves the short is upstream and saves you from pulling the bag. Trace the SRS harness behind the dash looking for splices, tape jobs, and chafe points against brackets. Remove any aftermarket tap you find rather than reinsulating it. We carry genuine OEM Nissan passenger airbags if the inflator turns out to be the fault. Related codes: B1065, B1067, B1617, B1040.
Trace the wiring and connectors first. If the module still holds the fault after the repair, mail it to us and we will clear it.
Genuine OEM, tested, and shipped ground from Jacksonville, Arkansas.
Do not see it listed? Request a part or call 501-988-0611.