SES reset

[Erich Zeppelin]

Hey guy's, bought a Toughbook with diagnostic's for my '99 5.4L my question is if my SES lamp comes on, do I scan with engine running or off? Also, after the repair do I reset the SES lamp with engine running or off?

 

[46L281GT]

you can do it either way. as long as the key is on.

 

[stamp11127]

Most tools will tell you what steps you will take once the unit is connected to the port. Clear codes is one option you can choose once the repair has been made or you could just clear it and wait for it to come back.

Go ahead and connect up so that you can familiarize yourself with the software. One feature that is helpful is usually called a snapshot and is set with trigger points. That would be a good thing to know how to use before needing it.

 

[nsperf]

Mostly depends on the diagnostic software and the vehicle PCM software.

Most OBDII PCS are bidirectional communications so certain changes such as resetting the SES light can be done with key on engine off ( KOEO ) or key on engine running ( KOER ).

Your software package will need to support the KOER resetting of the SES light.

Hope this helps