Failed smog test, OBDII connection issue + CEL afterward

[PandaBear]

A coworker of mine bought my father in law's camry (that 97 XLE V6), it turns out it failed smog because the OBDII port has no / bad connection or no power. Shortly after the smog check a CEL shows up. Without access to OBDII port what can we use to get the code out? The emission part of the smog pass well, and the engine runs fine though.

Anyone has experience on what to look for (other than the fuse)?

 

[Trav]

Test the connector for 12V and ground, if no power It may be something as simple as a blown fuse like on some GM when people drop their change in the holder and a penny shorts the lighter. The connector draws its power from that circuit.
You need to check every fuse if you don't have a diagram so you can isolate the circuit to a specific fuse.

 

[Chris142]

Usually the data port is on the same fuse as the lighter socket.

 

[clinebarger]

Should be a dedicated fuse on a older Toyota.....Check for a 7.5 amp labeled OBD in the fuse box located behind the drivers knee bolster. There is usually a removable panel or a storage compartment door that can be removed to access the fuse block.

 

[PandaBear]

Checked the fuse, looks good, swap it out with a near by same size (7.5amp) fuse for turn signals and confirmed it is not the fuse too.

Took the OBD connector out and take a look, nothing burnt or disconnected. It only has 4 wires into the connector and they all look clean and sturdy.

What is next before I ask a mechanic to take a look? Junkyard ECU / ECM swap?

 

[clinebarger]

A faulty ECU is a pretty remote possibility!

Pin 16 should have battery power, Pins 4 & 5 are Grounds, Pin 7 is the Serial Data line.