Well now that I am retired I must have too much time on my hands.

Ever since I first got my 97 exploder 4.0L OHV (2000) the O2 sensors will not register using the generic scan (regardless of which device I use).

I know they are there and are working because my fuel trims are within spec and the ready monitors for 02 set. The PCM will also set codes if I trigger the 02's

Using Ford Enhanced software I can request PIDs on the O2 and they will graph.

So my question is this, what could cause this sensor blackout??

 

I'm not an expert in OBD-II, but I'll ask a few questions anyway. When you say the O2 sensors won't register using the generic scan, are you referring to a datastream display rather than a "generic scan" for set diagnostic codes?

Understanding what tool/software you are using may help as well. It's possible the tool you have terms them differently, such as "HO2S" or "HEGO." Are there fields that are displayed that you have yet to figure out what they mean?

-Rod

 

If you re read my post I indicated that DTC codes will set when triggered and the associated ready monitors are set (have to pass spec before set ready).

I am unable to aquire DATA stream for the O2 sensors (only), all other sensors will generate and display live DATA. I am of course referring to the Generic OBDII scans as opposed to the enhanced Ford PID scan.

I have several, data links + laptop combination's, also several hand held scanners. All display or not the same information.

If I use the same computer combination with the Ford Enhanced PID software I am able to see and record the live data (Oscilloscope type/switching) from the O2 sensors.

So my question again, "why and how is generic OBDII data stream blacked out for the O2 sensors".

BTW,
This only happens on my 97, all others that I have scanned, 100+ show all live data for all sensors that are monitored.

I have been successfully using OBD, OBDII and CAN diagnostic equipment for the past 10+yrs.

I have been active in auto diagnostics, rebuild and repair (shadetree Ralley racing)since 1966. That is why I asked for EXPERT HELP.

Thanks in advance... P

 

I remember reading that certain OBD2 parameters do not read properly on 97 and 98 explorers. Just can't remember where I read that.

 

Shame on you for trying to help, Rod, when you're not AN EXPERT.........

That leaves me out too

 

I was not putting Rod down, just trying to eliminate pages of idle chatter and guess work as is evident if you read many threads in this forum. I am looking for valid diagnostic information.

Sorry if I offended anyone,

Now you can put me on the rotisserie if you like.......P

 

It is true, some parameters do not work correctly on '96-'98 systems unless you use the enhanced scan. The Early EEC-V systems did not fully comply with OBD-II standards. My brothers Aerostar won't let me read the O2 sensors either, but his does have fuel trim problems. His has no codes, but it does have a closed loop fault.

 

bump....

 

As mentioned, early OBDII implementations were not as comprehensive as the later versions.