'99 GS300 APP sensor output curve OK?
03-24-14, 02:47 AM
#1
Driver School Candidate
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'99 GS300 APP sensor output curve OK?
Here is my APP (Accelerator Pedal Position) sensor output voltage curve.
Can anyone tell me if this is within specification?
(This was measured at the ECU B2 connector pins, relative to the E2 ground reference.)
(the "lumps" in the curve are because the points are not evenly spaced, not dropouts)
The question is: are the absolute VPA / VPA2 and differential voltages within the range allowed by the ECU?
It is obviously working in basically the correct overall way, but my ECU is throwing the infamous P0121, P1120 codes and going into Limp Home Mode.
The ECU is stubbornly unhappy with something, but all the components seem to be working just as they should. It throws the codes when cold or hot.
> The TPS sensor has already been replaced. It's output looks similar to this (different voltages).
> Also, I connected battery voltage the the Throttle Control Actuator Motor (and clutch) and it opens and closed very briskly, in both directions, and with good force.
> The ECU has been removed and inspected. Looks shiny/new like the day it was made. No signs of damage or aging of any kind. Good solder joints, conformal coating, etc. All the connectors were slid on and off several times to restore good contact.
I'm thinking that if this APP sensor is within spec, then it has to be a failed A/D converter in the ECU. Unfortunately, the OBDII PID for this APP sensor seems to be unavailable to my ScanTools MX Bluetooth/Torque Pro.
Thanks,
Mark
Can anyone tell me if this is within specification?
(This was measured at the ECU B2 connector pins, relative to the E2 ground reference.)
(the "lumps" in the curve are because the points are not evenly spaced, not dropouts)
The question is: are the absolute VPA / VPA2 and differential voltages within the range allowed by the ECU?
It is obviously working in basically the correct overall way, but my ECU is throwing the infamous P0121, P1120 codes and going into Limp Home Mode.
The ECU is stubbornly unhappy with something, but all the components seem to be working just as they should. It throws the codes when cold or hot.
> The TPS sensor has already been replaced. It's output looks similar to this (different voltages).
> Also, I connected battery voltage the the Throttle Control Actuator Motor (and clutch) and it opens and closed very briskly, in both directions, and with good force.
> The ECU has been removed and inspected. Looks shiny/new like the day it was made. No signs of damage or aging of any kind. Good solder joints, conformal coating, etc. All the connectors were slid on and off several times to restore good contact.
I'm thinking that if this APP sensor is within spec, then it has to be a failed A/D converter in the ECU. Unfortunately, the OBDII PID for this APP sensor seems to be unavailable to my ScanTools MX Bluetooth/Torque Pro.
Thanks,
Mark
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sonyoor
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05-12-14 07:03 AM
