Can't connect through OBD port

[fyre82]

2000 Ranger 4.0 4x4
I have an intermittent check engine light for a slow O2 sensor, known malfunction. If it bothers me I turn it off with my Inova code reader.
Got the light again, went to connect the reader and it won't connect to the computer, hot, cold, key on/off, engine on/off. Tried it on my 03 Focus, works fine as it had previously on the Ranger.
Any ideas?

Thanks
Rich

 

[Spott]

2000 Ranger 4.0 4x4
I have an intermittent check engine light for a slow O2 sensor, known malfunction. If it bothers me I turn it off with my Inova code reader.
Got the light again, went to connect the reader and it won't connect to the computer, hot, cold, key on/off, engine on/off. Tried it on my 03 Focus, works fine as it had previously on the Ranger.
Any ideas?

Thanks
Rich

In order of probability, these are my suggestions:

1. A blown fuse for the OBD2 port. On my '97, it's fuse 5 at the instrument panel.

2. A damaged or corroded OBD2 connector.

3. A damaged or corroded wire or connector between the computer and the OBD2 port.

4. Internal damage to the PCM affecting the connections or communication to the OBD2 port.

I'd test and repair the possible problems in that order.

 

[RonD]

Check cigarette lighter fuse in cab fuse box, it also powers OBD port

Usually a 20 or 25amp fuse

 

[fyre82]

2000 is fuse 17, cigar lighter/Data Link Connector (DLC) 25a
The DLC threw me until I thought about it . . .
All good now.
Thank you, gentlemen.
Rich