B1325: Device Power Circuit Voltage

Circuit fault

What B1325 means

Restraint modules need a steady supply to run their internal checks and to hold enough energy to fire a device. The module watches its own supply voltage, and B1325 is what it stores when that voltage climbs too high or sags too low. The fault is about the feed itself rather than any airbag, belt, or sensor.

This code often arrives with a group of other restraint codes, because a module running on bad voltage misreads circuits it would otherwise pass. Fixing the power problem first can clear several codes at once and save a lot of unnecessary testing. A vehicle that sat on a weak battery, or one that was jump started roughly, is the profile that brings this code in most often.

Common causes

• A failing battery or corroded battery terminals
• A charging system overcharging or undercharging the vehicle
• A loose or corroded ground at the module or on the body
• Voltage drop from a corroded connector or a damaged supply wire
• A jump start, welding, or a dead short elsewhere that dragged the system voltage down

Crash data or hardware fault?

B1325 is a circuit code because it follows a live measurement, in this case the voltage on the module's own feed. It clears once the supply is correct. Crash data behaves nothing like that, since it is written into memory when a deployment happens and stays permanently regardless of any clearing attempt.

Does our reset clear it?

A reset does not correct a voltage problem out in the vehicle. The module measures its supply on every key cycle, and B1325 returns until the battery, charging system, or wiring is sorted out. Test and repair the power side first, then clear codes and see what remains. Our mail-in reset is for modules holding crash data or a stored internal fault.

Which makes throw it

GMC carries B1325 in our lookup, where the module monitors its own device power circuit voltage.

What to do next

Load test the battery and check charging system output before touching anything on the restraint system, since a weak battery explains this code and several others on the same scan. Clean the battery terminals and the module ground, then perform a voltage drop test on the supply circuit. Recheck codes after the power side is solid and diagnose whatever is still present. Related codes: B101D, B1327, B1B0F.