Re: PO410, RCM seems Good, Air Pump works when Jumped ????
What happens if you place a ground on Pin 38 of connector 4 on the PCM ?
( This is what activates the air pump relay )
1. Make sure you have 12v on connector E pin 5 or connector A pin 3 of the RCM.
2. If that makes the pump run, then the PCM is at fault.
3. If it does NOT make the pump run, then you have faulty wiring.