LS2 E40 no throttle movement

[cmtcuda]

LS2 swap good pedal but no throttle movement
Just swapped an LS2 from 2006 TBSS. Disabled VATS, other than that the tune is completely stock. The pedal voltage sweeps when depressed, but no throttle movement. I have done a search and i am at a loss.
Thanks in advance for any help.

0x7E8: P0107 - Manifold Absolute Pressure/BARO Sensor Low (Pending, Current)
0x7E8: P0689 - ECM/PCM Power Relay Sense Circuit Low (SES, Pending)
0x7E8: P2138 (Pending, Current, Old, History)
0x7E8: U1064 (Pending, Old)
0x7EA: U0100 - Lost Communication With ECM/PCM A (Pending

[blindsquirrel]

Do you have access to wiring diagrams and diagnostics info?

Describe, in as much detail as you like (more is better), your ignition switch setup and how constant/switched power & grounds are supplied to the ECM (which pins going to what).

[cmtcuda]

This is an aftermarket wiring harness. I have had a lot of problems with almost every aspect of the process. The company is out of my local area so logistics have been a nightmare. the customer service is fantastic and they have tried to help me over the phone as much as possible.
they have sent me wiring diagrams. they look like Alldata WDM.

ALL GROUNDS DIRECT TO BATTERY, IGN 12V FROM FUSE BLOCK, AND 12V BATT DIRECT TO BATTERY HARNESS

i have reference 5v at the throttle body, but no fluctuation when pedal is pushed.

C1-18 12V IGN
C1-19 12V IGN
C1-20 12V BATT
C1-35 white from pedal
C1-22 DK BLUE FROM PEDAL
C1-41 LT BLUE FROM PEDAL
C1-8 PURPLE FROM PEDAL
C1-7 BROWN FROM PEDAL
C1-29 TAN FROM PEDAL

thank you for the response

[blindsquirrel]

C1 #14 should also be a fused (15A), switched IGN. In the stock fuse box label that fuse is called "ETC".

screenshot.15-05-2020 20.48.45.png

[cmtcuda]

I have added switched 12v to C1-14.
Now when Turn ignition on I get flutter from the throttle body and then nothing.

[blindsquirrel]

Well it sure wasn't ever going to work without that.

Clear the codes; which ones come back?

[cmtcuda]

Here are the current DTC's
0x7E8: P2119 (Pending, History)
0x7E8: P2135 (Pending, Current, Old, History)
0x7E8: P2138 (Pending, Current, Old, History)
0x7EA: U0100 - Lost Communication With ECM/PCM A (Permanant)

[blindsquirrel]

DTC P2119 Throttle Closed Position Performance

Circuit Description
The engine control module (ECM) controls the throttle valve by applying a varying voltage to the throttle actuator control motor. The ECM monitors the actual throttle valve position using throttle position (TP) sensor 1 and 2. If the ECM detects the throttle valve did not return to the rest position within a calibrated time, this DTC sets.

Conditions for Setting the DTC
The ECM determines that the throttle valve did not return to the rest position within 720 milliseconds.

Diagnostic Aids
? Use the J 35616 Connector Test Adapter Kit for any test that requires probing the ECM harness connector or a component harness connector.
? Inspect for a condition in which the throttle valve may have been held open. For example, ice may have formed in the throttle bore causing the throttle valve not to close. Observe the Freeze Frame/Failure Records.
? The throttle valve is spring loaded to a slightly open position. The throttle valve should be open approximately 18-24 percent. This is referred to as the rest position.
? The throttle valve should not be completely closed or open any more than a specified amount.
? The throttle valve should move open and to the closed position without binding under the normal spring pressure.
? The throttle should NOT be free to move open or closed WITHOUT spring pressure.
? The scan tool has the ability to operate the throttle control system using the TP function located in the TAC System menu. This function operates the throttle valve through the entire range in order to determine if the throttle actuator control (TAC) system operates correctly.
? For an intermittent condition, refer to Testing for Intermittent Conditions and Poor Connections .

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DTC P2135 Throttle Position (TP) Sensor 1-2 Correlation

Circuit Description
The throttle position (TP) sensors 1 and 2 are located within the throttle body assembly. The TP sensors share a common 5-volt reference circuit and a common low reference circuit. The 5-volt reference circuit is also shared with the accelerator pedal position (APP) sensor 2. The 5-volt reference voltage is supplied on 2 separate engine control module (ECM) terminals, but the terminals are connected internally to the same voltage supply. Each TP sensor has an individual signal circuit, which provides the ECM with a signal voltage proportional to throttle the plate movement. When the throttle plate is in the closed position, the TP sensor 1 signal voltage is near the low reference and increases as the throttle plate is opened. The TP sensor 2 signal voltage at closed throttle is near the 5-volt reference and decreases as the throttle plate is opened. If the ECM detects that the TP sensors are not within a predicted value from each other, DTC P2135 sets.

Conditions for Setting the DTC
The ECM detects that the difference between TP sensor 1 and TP sensor 2 is more than the predicted value for less than 1 second.

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DTC P2138 Accelerator Pedal Position (APP) Sensor 1-2 Correlation

Circuit Description
The accelerator pedal position (APP) sensor is made up of 2 sensors that are housed inside one assembly. The engine control module (ECM) supplies a separate 5-volt reference circuit and a low reference circuit for each of the sensors. The 5-volt reference for APP sensor 1 is supplied from the same source in the ECM as the 5-volt reference for the mass air flow (MAF) sensor and the fuel tank pressure (FTP) sensor. The 5-volt reference voltage for all of the sensors is supplied on separate ECM terminals, but the terminals are connected internally to a voltage supply. The APP sensor 1 sends a signal from the sensor to the ECM indicating the accelerator pedal position. The ECM actuates the throttle plates based on this information. If the ECM detects that the APP sensors are not within a predicted value from each other, DTC P2138 sets.

Conditions for Setting the DTC
The ECM detects that the difference between APP sensor 1 and APP sensor 2 is more than the predicted value for less than 1 second.

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So, you have what looks to be a problem on the APP side, and on the TP side, probably causing the throttle body to do something unexpected which sets the P2119... or, a physical problem with the movement of the blade itself. Can you move the blade by hand, feel normal? You are using the TBSS pedal, right? And not just something else that fit better?

screenshot.15-05-2020 22.27.07.png

screenshot.15-05-2020 22.26.56.png

[cmtcuda]

I am using the TBSS pedal, but I am using an aftermarket gold blade throttle body. I can move the throttle body by hand and was able to move it with 12v

[blindsquirrel]

Double-triple-ultra-mega-check your pinouts, the codes indicate problems between ECM & both the APP and TB.

[cmtcuda]

I will go through the whole pin out in the morning. Thank you for your help.

[cmtcuda]

This is how the throttle body is wired. I for got to mention I am using ls3 heads and manifold anf throttle body. I tried to find a pin out for the ls3 throttlebody, but couldnt find any information. I don
A=YELLOW
B=WHITE
C=BROWN
D=BLACK
E=BLUE
F=PURPLE

[Lakegoat]

The LS2 throttle body and the gold blade have different wiring. Don't know where to find it. Maybe look on LS1GTO forum. It may be there.

[blindsquirrel]

2009 Corvette LS3 E38
A: X2 pin5 TAC Motor Control 2
B: X2 pin6 TAC Motor Control 1
C: X2 pin35 Low Ref
D: X2 pin65 TP Sensor 1 Signal
E: X2 pin3 5-Volt Ref
F: X2 pin63 TP Sensor 2 Signal

If you translate those assignments to the '06 E40 pinouts it turns into...
A: C2 pin60 TAC Motor Control 2
B: C2 pin63 TAC Motor Control 1
C: C2 pin36 Low Ref
D: C2 pin31 TP Sensor 1 Signal
E: C2 pin41 5-Volt Ref
F: C2 pin29 TP Sensor 2 Signal

Ignore wire colors except to verify it's going from the right TAC pin to the right ECM pin.

I can't find any info about the LS3 TP sensor configuration, sometimes GM swaps those around, makes them go same direction or opposite directions. That TB may not be compatible even with the correct pinning.

[cmtcuda]

The pinouts for the APP and the throttle body are correct. I have 5v to the pedal, and the position sweeps when depressed. I do not have 5v to the throttle body, in fact the throttle body doesnt get anything from the computer. Is my computer bad?

[blindsquirrel]

You mean, you verified that the wire at throttle body cav 'E' is the same wire as ECM C2 41? And backprobing C2 41 with key-on, you have no 5vref?

If that's the case, I would be real tempted to confirm that wire isn't shorted to GND, and temporarily jumper over to another 5vref source and see if the throttle suddenly works.

Potential 5vref candidates that may not even be in use in your application, you can just move the wire at C2 41 over to one of these:
C1 30 - A/C Pressure Sensor
C1 31 - Fuel Tank Pressure Sensor
C3 15 - Brake Booster Vacuum Sensor
C3 35 - EV Fan Speed Sensor

[cmtcuda]

Yes I verified to the ECU. I will run a from the C3 connector. It is almost empty. Thanks

[cmtcuda]

What should I be reading at the TAC motor control pins?

[blindsquirrel]

It depends. Polarity and voltage applied varies according to where the blade is compared to where the ECM wants it to be.

[cmtcuda]

Is there supposed to be 12v supplied to the TB? If I put the pedal to the floor wil I see 12v to any of the TB pins