Well --- almost three years into code P2122, I finally found the trouble maker ... the sto-o-o-o-pid fan.
Naturally - after running an oscilloscope on the throttle rheostats and checking both resistance ramps and the mysterious "Null Point" --- I dismissed the foot throttle (APP) as any reason at all for the code; everything was right where it needed to be.
I suspected something was taking a hit off the 5V power supply from the ECM but I couldn't prove it since it was so intermittent ... the fan was never in my suspicion.
... this is not the whole truth although it DOES run off the available 5VDC system coming out of the ECM.
The final clue was that the fan decided all on it's own to go into MAX-ON Mode.
Here's the sketchy part ---> I cannot find a decent fan assembly and I have to install a brown box, house brand fan from O'Reily's.
I'll be posting the success or failure of this fan - and that might be fun to help debunk or support the nay-saying about off-brand parts.
(OK --> I didn't say to use off-brand spark plugs. That would be bad.)
/
Naturally - after running an oscilloscope on the throttle rheostats and checking both resistance ramps and the mysterious "Null Point" --- I dismissed the foot throttle (APP) as any reason at all for the code; everything was right where it needed to be.
I suspected something was taking a hit off the 5V power supply from the ECM but I couldn't prove it since it was so intermittent ... the fan was never in my suspicion.
....The P2122 OBD-II trouble, or fault, code means that the vehicle's on-board computer has detected low voltage in the throttle position sensor (TPS), which is usually below 0.17 volts. Code P2122 is defined as a Throttle/Pedal Position Sensor/Switch "D" Circuit Voltage is Low
... this is not the whole truth although it DOES run off the available 5VDC system coming out of the ECM.
The final clue was that the fan decided all on it's own to go into MAX-ON Mode.
The roaring told me all was not well and I got the P2122 instantly - it refused to clear until the fan speed dropped into a more-or-less normal RPM and I got to drive away at that point.
Here's the sketchy part ---> I cannot find a decent fan assembly and I have to install a brown box, house brand fan from O'Reily's.
I'll be posting the success or failure of this fan - and that might be fun to help debunk or support the nay-saying about off-brand parts.
(OK --> I didn't say to use off-brand spark plugs. That would be bad.)
/