Operation CHARM: Car repair manuals for everyone.

EGR Flow Test Count

Scan Tool Range 0 to 255. Indicates the number of EGR flow test samples collected during the current ignition cycle. The maximum number of samples allowed is 1 during normal operation. If the PCM battery feed has been disconnected or a DTC P0401 has been cleared, several EGR flow test samples will be allowed during the next ignition cycle. This is to allow repair verification during a single ignition cycle.