I've been searching and calling around for some time now to no avail attempting to solve a problem that a mechanic I spoke to said I "may be the only person in the world experiencing this right now."

The problem has to do with my OBD output (I've tried on many different scan tools, but not HDS/HIM).

When selecting OBD mode $01 I have only 4 data points:

DTC_CNT
Etc
Rpm
Vss

This seems obviously not correct to me. The reason I have discovered this is that my I/M readiness monitors are not setting.

When I view the monitors in mode $01 I see the following:

Misfire monitor - N/A
Fuel system mon - N/A
Comp. Component - OK
Catalyst mon - N/A
Htd catalyst - N/A
Evap system mon - N/A
Sec air system - N/A
A/c refring mon - N/A
Oxygen sens mon - N/A
Oxygen sens htr - N/A
Egr system - N/A

This would indicate that my car has no ability to set the monitors as they do not exist in the system. However, in mode $08 (for some reason) I get 30 live data points. Not only that, the following monitors are set:

Misfire Monitor, OK
Fuel system mon, OK
Comp. Component, OK
Catalyst Mon, OK
Htd catalyst, N/A
EVAP system mon, INC
Sec Air System, N/A
A/C refring mon, N/A
Oxygen sens mon, OK
Oxygen sens htr, OK
EGR system, OK

Per the CA DMV, I can afford to not pass the EVAP system monitor check. By that logic I should be able to pass the smog check.

But I failed. I assume that this is because the smog check uses mode $01 data.

Has anyone ever heard of such a problem? Could it be the ECU?

 

I've done the DLC Circuit troubleshoot procedure outlined by my car's Chilton manual:

https://i.imgur.com/XesTkv9.png
https://i.imgur.com/dr1oy17.png

I don't have a known good ECU/ECM/PCM to test with, so I had to skip those parts. But everything involving continuity and voltage checked out.

Visually, the connections look clean and seem correct.

I'm out of (simple) ideas. The next thing I have in mind is CAN sniffing or pulling the ECU and giving it a visual inspection. Has anyone done either of those things before?

 

For Honda/Acura:

To check if the readiness codes are set, turn the ignition switch to the ON (II) position, without starting the engine. The MIL will come on for 20 seconds. If it then goes off, the readiness monitors are set. If it blinks five times, the readiness monitors are not set.

 

I've confirmed that the monitors are not set before.

The MIL blinks 5 times, but I have no codes and data while driving seems nominal and accurate.

If the car is relying on mode $01 data, then there are many monitors not ready/not found. If the car is relying on mode $08 data, then only the EVAP monitor is not set.

Why there is a difference is beyond me.

However, in CA, I am allowed to pass smog without EVAP monitor setting. Despite that, I failed the smog check. The paper given to me cited the oxygen sensor, which I verified was set in mode $08 immediately upon pulling out of the lot, but not in mode $01.