Possible causes
– Loose or poor battery terminal connection
– Low battery charge
– ECM power supply circuit is open or shorted
– ECM Programing
– Faulty ECM
– Low battery charge
– ECM power supply circuit is open or shorted
– ECM Programing
– Faulty ECM
Tech description
Start by charging the vehicles battery and clean terminal, once the battery is charged and the terminals are clean and secure, erase code. If the code comes back ON you may have to reprogram or replaced ECM
When is the obd code mean?
Indicates the ECM has experienced an internal memory fault.
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
– Engine may not start
– Engine may not start
P0603 FORD OBD Code Description