Corolla OBD Failure

Good news!

I popped over to Autozone on the way home and their OBD-II scanner
wouldn't pick up anything either - just dead. They let me play with
the scanner for a bit, so I jiggled some wires but no luck...

Once I got home, I tried to measure the voltage and resistance across
the various terminals that Ray had specified and NOT even one pin was
"live" - no voltage, infinite resistance... I was glad in a way that
every pin was reading open - since I was confident that a connector was
not in place somewhere along the harness.

I took off the cover under the steering column and lo and behold, right
in front of me was a disonnected harness. The DLC3 connector is on an
8" (or thereabouts) short harness. The other end connects to the main
harness. That connector was completely undone. I imagine the
connector was left undone when some work had been done on the car -
since you have to undo the connector to remove the plastic cover from
the car.

I plugged it in, checked the pins, and the readings "almost" as Ray had
specified. For me Pin #7 voltage did not go on/off, other pins checked
out as described.

I popped back to autozone, had the guys recheck and their scanner
worked fine and reported "No Codes Found".

So now I'm off to the emissions place tomorrow again. Hopefully they
won't pull their "This repair has to be certified by an authorized shop
card" on me.

Thank you all for your help!

Nirav
97 Corolla DX, 72k

"njmodi" <njmodi2@yahoo.com> wrote in message
news:1120091916.566206.173340@g44g2000cwa.googlegroups.com...[color=blue]
> Good news!
>
> I popped over to Autozone on the way home and their OBD-II scanner
> wouldn't pick up anything either - just dead. They let me play with
> the scanner for a bit, so I jiggled some wires but no luck...
>
> Once I got home, I tried to measure the voltage and resistance across
> the various terminals that Ray had specified and NOT even one pin was
> "live" - no voltage, infinite resistance... I was glad in a way that
> every pin was reading open - since I was confident that a connector was
> not in place somewhere along the harness.
>
> I took off the cover under the steering column and lo and behold, right
> in front of me was a disonnected harness. The DLC3 connector is on an
> 8" (or thereabouts) short harness. The other end connects to the main
> harness. That connector was completely undone. I imagine the
> connector was left undone when some work had been done on the car -
> since you have to undo the connector to remove the plastic cover from
> the car.
>
> I plugged it in, checked the pins, and the readings "almost" as Ray had
> specified. For me Pin #7 voltage did not go on/off, other pins checked
> out as described.
>
> I popped back to autozone, had the guys recheck and their scanner
> worked fine and reported "No Codes Found".
>
> So now I'm off to the emissions place tomorrow again. Hopefully they
> won't pull their "This repair has to be certified by an authorized shop
> card" on me.
>
> Thank you all for your help!
>
> Nirav
> 97 Corolla DX, 72k
>[/color]
It sounds like your problem is solved! The pulsing voltage from Pin #7 is
only when it is relaying info.
--
Ray O
correct the return address punctuation to reply

Good info. once again. I appreciate your help.

Nirav