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A sensor's regulated reference supply — usually five volts — shorted to battery voltage, which is worth separating from an ordinary open or earth short because it is the version that can destroy the module.

The reference is a regulated output, not a passive line. Feeding twelve or fourteen volts back into it drives current the wrong way through the regulator, and the module's protection either shuts the supply down or the regulator fails. Every sensor sharing that reference then reads wrongly at once, so the codes name half a dozen unrelated sensors and the temptation is to suspect the module.

That cluster is the diagnostic gift. Several sensors on one reference failing together locates the fault on the shared wire, not in any sensor. Disconnect sensors one at a time with the reference monitored — the reading recovering as one is unplugged names the culprit. The short is usually where a reference wire runs alongside a switched twelve-volt feed in the same loom and both have chafed against a bracket. Repair the chafe rather than only the sensor, or the new one meets the same voltage.