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2006 X350 at ~107K miles, displayed "Engine Systems Fault" and subsequently had very rough idle. Code scan revealed the following (P050B is years old and just never been 'fixed')
============1==============
U0401(92)
Raw code: C40192
ECU: 768[Archive (inactive)]
Status: Confirmed, Test failed since last DTC clear
Invalid data received - engine control module (ECM)
============2==============
U0401(64)
Raw code: C40164
ECU: 768[Archive (inactive)]
Status: Confirmed, Test failed since last DTC clear
Invalid data received - engine control module (ECM)
============3==============
P061A(29)
Raw code: 061A29
ECU: Engine control unit[Archive (inactive)]
Status: Test failed since last DTC clear
Engine control module (ECM), engine torque - performance problem
============4==============
P061A(64)
Raw code: 061A64
ECU: Engine control unit[Archive (inactive)]
Status: Test failed since last DTC clear
Engine control module (ECM), engine torque - performance problem
============5==============
P050B(84)
Raw code: 050B84
ECU: Engine control unit[Archive (inactive)]
Status: Test failed since last DTC clear
Ignition timing, cold start - performance problem
============6==============
P2105(00)
Raw code: 210500
ECU: Engine control unit[Archive (inactive)]
Status: Confirmed, Test failed since last DTC clear
Throttle actuator control (TAC) system - forced engine shut down mode
============7==============
P2105
Raw code: 2105
ECU: Engine control unit
Status: Confirmed
Throttle actuator control (TAC) system - forced engine shut down mode
I decided to focus on P2105 first but the X350 manual is not very descriptive
During test of the accelerator pedal, I noticed all readings seemed correct EXCEPT the "Commanded Throttle Actuator" which was very noisy.
Here is the Commanded Throttle Actuator with no input on the accelerator pedal, it jumps around erratically.
And here are the other throttle position readouts with me stepping on the throttle. You can see the Commanded Throttle Actuator has no correlation. All tests are done with engine off.
Can I get some insight into what all this means? I'm not sure what the 'Commanded Throttle Actuator' actually refers to. My guess is that these codes probably refer to either a malfunction in the TPS sensor in the Throttle Body or APP sensor in the Accelerator Pedal, but I'm at a loss as to how to pinpoint the fault. I have the updated Throttle Body with the bolted on TPS.
commanded throttle actuator is what it says.....where the ecm wants the throttle motor to be. these don't have a bolted on TPS it's on the same connector as the motor.
2006 is the first year for panpag, p050b and p061a were both known by june of that year. reflash the ecm with the latest calibration, if that doesn't solve the problem use your brain to figure out what sensors are used in a torque calculation rationality check
"invalid" torque calculation -> ecm no like > throttle limp home -> car no work
04-15-2023 | 08:05 PM
2006 XJ8 - P2105 p061A U0401 - Throttle issue??
