Help please
Asked by Tequilla Apr 03, 2016 at 11:10 AM about the 2003 Chevrolet Trailblazer LT 4WD
Question type: Maintenance & Repair
Okay the diagnostic computer puts up these three
code
P1523
P1515
P1516
Diagnostic Computer put them three codes up.
Crank\Cam Sensor reading not showing voltage
going through to the injectors...
8 Answers
P1523 CHEVROLET - Electronic Throttle Control Throttle Return... Possible causes... - Dead or weak battery - Faulty Throttle Actuator Control (TAC) module - Throttle Actuator Control (TAC) module harness is ope or shorted - Throttle Actuator Control (TAC) module circuit poor electrical connection... Possible symptoms... - Engine Light ON (or Service Engine Soon Warning Light) - No throttle response... P1523 Chevrolet Description.... The Throttle Actuator Control (TAC) module contains data which is essential for proper TAC operation. The TAC module continuously test the integrity of this data. When the TAC module is unable to write or read data to and from random access memory (RAM), or the TAC module is unable to correctly read data from the flash memory or and internal TAC module processor fault is detected and the Detected Trouble Code (DTC) is set..... P1515 CHEVROLET - Control Module Throttle Actuator Position Performance... Possible causes... - Poor connection at the Throttle Actuator Control (TAC) module - Faulty TAC module - Faulty Throttle Pedal Position (TPP) or Throttle Position (TPS) sensors - Binding or bent throttle plate-failed throttle body... The Powertrain Control Module (PCM) has detected a throttle plate out of position based on commanded and actual throttle plate position... Possible symptoms... - Engine Light ON (or Service Engine Soon Warning Light)... P1515 Chevrolet Description... The Throttle Actuator Control (TAC) system uses vehicle electronics and components to calculate and control the position of the throttle blade. This eliminates the need for a mechanical cable attachment from the accelerator pedal to the throttle body. This system also performs the cruise control functions as well. The TAC system components include, but are not limited to the following: - The accelerator pedal position (APP) sensors - The throttle body - The powertrain control module (PCM)... Each of these components interface together to ensure accurate calculations and control of the throttle position (TP)... Throttle Body Assembly... The throttle body for the throttle actuator control (TAC) system is similar to a conventional throttle body with several exceptions. One exception being the use of a motor to control the throttle position instead of a mechanical cable. Another exception is the throttle position (TP) sensor. The TP sensor is mounted in the throttle body assembly. The TP sensor is 2 individual TP sensors within the throttle body assembly. Two separate signal, low reference, and 5-volt reference circuits are used to connect the TP sensors and the powertrain control module (PCM). TP sensor 2 signal voltage increases as the throttle opens. TP sensor 1 signal voltage decreases as the throttle opens.... P1516 CHEVROLET - Throttle Actuator Control Module Throttle Actuator Position Performance... Possible causes.... - Faulty Throttle Actuator Control (TAC) module - Throttle Actuator Control (TAC) module harness is open or shorted - Throttle Actuator Control (TAC) module circuit poor electrical connection - Check Throttle Actuator Control (TAC) module connector for water - Binding or bent throttle plate-failed throttle plate-failed throttle body.... Some Tech notes.... The Engine Control Module (ECM) has detected an out of range condition between the predicted and actual throttle position. Possible symptoms... - Engine Light ON (or Service Engine Soon Warning Light) - No throttle response... P1516 Chevrolet Description... The Engine Control Module (ECM) is the control center for the Throttle Actuator Control (TAC) system. The ECM determines the drivers intent and then calculates the appropriate throttle response. The ECM achieves throttle positioning by providing a pulse width modulated voltage to the TAC motor. The TAC system uses the following circuits for Motor control 1 and Motor control 2. Two processors are also used to monitor the TAC system data. Both processors are located within the ECM. Both processors monitor each other's data to verify that the indicated throttle position is correct.
But why is it locking me out...that's what I don't understand.. Is that what happens when the throttle body bad..
Where would I find the TAC and how could I test it?
You vehicle does not have a throttle cable for acceleration. It is worked by almost like a rheostat. There are components down on the gas pedal and the throttle body which controls the acceleration. I'm trying to find a picture of the Throttle Actuator Control.
http://www.carid.com/2003-chevy-trailblazer-fuel-delivery-parts/bm-overdrive-transmission-control-11100024.html
Will the diagram help me fix it without coming out of pocket alot...cause this was my situation, I parked at a friend's house my truck was running just fine, started just fine and everything, but when I parked at my friend's house and shut my truck off it wouldn't start back..it sound like it wasn't getting fire..I had no pressure in the front or the back....hooked it up to a computer and atbfurst it put up a fuel pump code, so we changed the fuel pump, now I get the pressure in the back just not the front...hooked it back up to the computer that's when it shot out the p1523, p1515, p1516... I don't want to put alot of money into it and it be something simple like a bad connection...
Can't guarantee that, but everything is pointing to the TAC system. I have not worked on those.
Where is that located, by the module or by the acceleration paddle