Check engine lite is on, power lost lite is on. code p1276comes up. replaced throttle body, but no change. volts at vac fuse 14 both sides. will not accelerate over 1800 rpm's. 2004 trailblazer with 6cyl.

DTC P0123 Throttle Position (TP) Sensor 1 Circuit High Voltage

Circuit Description
The throttle body assembly contains 2 throttle position (TP) sensors. The TP sensors are mounted to the throttle body assembly and are not serviceable. The TP sensors provide a signal voltage that changes relative to throttle blade angle. The engine control module (ECM) supplies the TP sensors with a common 5-volt reference circuit , a common low reference circuit, and 2 independent signal circuits.
The TP sensors have opposite functionality. The TP sensor 1 signal voltage increases from below 1 volt at idle to above 4 volts at wide open throttle (WOT). The TP sensor 2 signal voltage decreases from above 4 volts at idle to below 1 volt at WOT.
If the ECM detects TP sensor 1 signal voltage is too high, this DTC sets.


This is why you need to take it to a qualified repair shop that has the diagnostic knowledge to find the problem , you have no clue what it takes to diagnose these type problem .


Test Description
The numbers below refer to the step numbers on the diagnostic table.
This step verifies that a condition exists.
This step tests the signal circuit for a short to voltage. If the scan tool displays a voltage after the TP sensor is disconnected, the circuit is shorted to a voltage.
This step tests for high resistance in the low reference circuit of the TP sensor. The ECM must be completely powered down to obtain an accurate resistance reading. It may take up to 30 minutes for the ECM to power down after the ignition key is removed. Removal of the ECM fuse, or the PCM/ETC fuse, allows the ECM to power down completely.
This step tests the low reference circuit for a short to voltage.
Step
Action
Values
Yes
No
Schematic Reference: Engine Controls Schematics
Connector End View Reference: Engine Control Module Connector End Views or Engine Controls Connector End Views
1
Did you perform the Diagnostic System Check - Vehicle?
--
Go to Step 2
Go to Diagnostic System Check - Vehicle
2
Turn ON the ignition, with the engine OFF.
Observe the TP sensor 1 voltage parameter with a scan tool.
Is the voltage more than the specified value?
4.5 V
Go to Step 5
Go to Step 3
3
Observe the DTC information with a scan tool.
Did DTC P0223 fail this ignition?
--
Go to Step 5
Go to Step 4
4
Observe the Freeze Frame/Failure Records for this DTC.
Turn OFF the ignition for 30 seconds.
Start the engine.
Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition?
--
Go to Step 5
Go to Diagnostic Aids
5
Turn OFF the ignition.
Notice: Refer to Disengaging Connectors Notice in the Preface section.
Disconnect the throttle body harness connector. Refer to Throttle Body Assembly Replacement .
Turn ON the ignition, with the engine OFF.
Observe the TP sensor 1 voltage parameter with a scan tool.
Is the voltage less than the specified value?
0.1 V
Go to Step 6
Go to Step 9
6
Measure the voltage between the 5-volt reference circuit of the throttle position (TP) sensor and the engine control module (ECM) housing with a DMM.
Is the voltage more than the specified value?
5.2 V
Go to Step 10
Go to Step 7
7
Turn OFF the ignition.
Remove the ECM fuse, or the PCM/ETC fuse, from the underhood fuse block.
Notice: Do NOT use a test lamp to test the continuity of the circuit. Damage to the control module may occur due to excessive current draw.
Measure the resistance from the low reference circuit of the TP sensor to the ECM housing, with a DMM.
Is the resistance less than the specified value?
5 ohms
Go to Step 12
Go to Step 8
8
Install the ECM fuse into the underhood electrical center.
Turn ON the ignition with the engine OFF.
Measure the voltage between the low reference circuit of the TP sensor and the ECM housing, with a DMM. Refer to Circuit Testing .
Is the voltage less than the specified value?
1 V
Go to Step 11
Go to Step 14
9
Test the signal circuit of the TP sensor 1 for a short to voltage. Refer to Circuit Testing and Wiring Repairs .
Did you find and correct the condition?
--
Go to Step 17
Go to Step 13
10
Important: The engine control module (ECM) for this engine is not equipped with 5-volt reference DTCs. The 5-volt reference circuits are internally and externally connected at the controller. Other sensors that share the 5-volt reference circuit may also have DTCs set. Disconnecting a sensor on the shared 5-volt reference circuit may isolate a shorted sensor. Review the electrical schematic and diagnose the shared circuits and sensors.
Test the 5-volt reference circuit of the TP sensor and all shared 5-volt reference circuits for a short to voltage. Refer to Circuit Testing and Wiring Repairs .
Did you find and correct the condition?
--
Go to Step 17
Go to Step 13
11
Turn OFF the ignition.
Disconnect the ECM.
Test the low reference circuit of TP sensor for an open or a high resistance. Refer to Circuit Testing and Wiring Repairs .
Did you find and correct the condition?
--
Go to Step 17
Go to Step 13
12
Test for shorted terminals and for poor connections at the TP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .
Did you find and correct the condition?
--
Go to Step 17
Go to Step 15
13
Test for shorted terminals and for poor connections at the ECM. Refer to Circuit Testing and Connector Repairs .
Did you find and correct the condition?
--
Go to Step 17
Go to Step 16
14
Important: The control module and/or the TP sensor may be damaged if the circuit is shorted to battery positive voltage.
Repair the short voltage in the low reference circuit of TP sensor. Refer to Wiring Repairs .
Did you complete the repair?
--
Go to Step 17
--
15
Replace the throttle body assembly. Refer to Throttle Body Assembly Replacement .
Did you complete the replacement?
--
Go to Step 17
--
16
Replace the ECM. Refer to Control Module References for replacement, setup, and programming.
Did you complete the replacement?
--
Go to Step 17
--
17
Clear the DTCs with a scan tool.
Turn OFF the ignition for 30 seconds.
Start the engine.
Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition?
--
Go to Step 2
Go to Step 18
18
Observe the Capture Info with a scan tool.
Are there any DTCs that have not been diagnosed?
--
Go to Diagnostic Trouble Code (DTC) List - Vehicle
System OK

I would go back to the power and ground cables. First, you checked grounds and cleaned them. Do you have all the grounds in place. From the battery, you should have a ground from the battery to body, battery to the engine and from the engine to the body. Positive side should be from the battery to the alternator, battery to the starter and battery to the under hood fuse panel. Check these cables also. Since you 14 volts going to 12 volts, I would suspect a engine to body ground or corrosion at the fuse panel plugs/connectors.

check eng. lite?intake hose no cracks and installed correctly and tight to throttle body. a must check fuel pressure regulator,can pull vac line while running will leak fuel,replace.exaust restriction?

pass the scanner/computer for better diagnostic. DO not waste your time and money. The electronic in the car now is very complicated. MAYBE the computer BCModule can be faulty.
God bless you

Could be several things, including a vac leak, a faulty EGR valve, or low fuel pressure.
If the check engine light is on I would start with getting it scanned for trouble codes. If not, check the fuel pressure with a gauge.

Throttle body injection? replace the injectors. First check for power to them. 12 volts from one of the wires with key on

You don't say if the codes are same after fan clutch replacement, if you still get the P0526, you may have a bad clutch or a defective wire harness.
For the P0106, this is indicating a problem in the MAP sensor area. In order to check the MAP sensor you need a highend scan tool. But before changing anything, do a thorough cleaning of the throttle body first, make sure to clean the front and rear sides. Also disconnect the battery while doing the cleaning, this will reset the computer to factory defaults and allow it to relearn to the cleaned throttle body.

YOU MAY GET A PEDAL POSITION SENSOR CODE AND A THROTTLE POSITION SENSOR INPUT CODE. IF YOU GET THESE CODES, THEN CHANGE THE THROTTLE BODY/THROTTLE POSITION SENSOR. SINCE YOUR THROTTLE POSITON SENSOR IS PART OF THE BODY, YOU MUST CHANGE THE THROTTLE BODY BECAUSE THE T.P.S. IS RIVETED TO IT AND CANNOT BE PURCHASED SEPARATELY. IT IS A DEALER PART ONLY. P.S. BE CAREFUL IF YOU CHANGE THIS PART YOURSELF DUE TO THE FACT THAT COOLANT RUNS THROUGH THE BODY TO HELP DISSIPATE HEAT. HOPE THIS HELPS. PLEASE KEEP ME POSTED. THANK YOU FOR AN HONEST RATING AND FOR USING FIX-YA.

you should have 12 volts at battery with engine off.
should have about 14 volts if charging.
what are you getting?

check fuse 20 in power distribution box on left side of engine compartment.