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Having all kinds of issues with my lbz. It's throwing a p0698 code and is my understanding is it could be a throttle position sensor, vane position sensor and map sensor. I've read that I need to check the number 3 circuit on ecm and unplug each sensor. Question is how do I know which pin to check on ecm?
 

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DTC P0698 or P0699

Diagnostic Instructions



DTC Descriptors

DTC P0698

  • 5-Volt Reference 3 Circuit Low Voltage
DTC P0699

  • 5-Volt Reference 3 Circuit High Voltage
Diagnostic Fault Information




Circuit/System Description

These 5-volt reference circuits are independent of each other outside the engine control module (ECM), but are bussed together inside the ECM. Therefore, a circuit condition on one sensor 5-volt reference circuit may affect the other sensor 5-volt reference circuits. The ECM monitors the voltage on the 5-volt reference circuit.

Conditions for Running the DTC




  • The ignition is ON.
  • Diagnostics run continuously.
Conditions for Setting the DTC

P0698


  • The ECM detects the 5-volt reference 3 circuit voltage is less than 4.7 volts.
  • The above condition is present for 2 seconds.
P0699

  • The ECM detects the 5-volt reference 3 circuit voltage is more than 5.2 volts.
  • The above condition is present for 2 seconds.
Action Taken When the DTC Sets

DTCs P0698 and P0699 are Type A DTCs.

Conditions for Clearing the MIL/DTC

DTCs P0698 and P0699 are Type A DTCs.

Circuit/System Verification

Engine starts and runs.

Circuit/System Testing


  1. Turn OFF the ignition for 60 seconds or until the ECM powers down.
  2. Disconnect the accelerator pedal position (APP) sensor.
  3. Turn ON the ignition, with engine OFF and measure the voltage from the 5-volt reference circuit of the APP sensor 1 to a good ground with a DMM.
  • If the voltage measures 4.7-5.2 volts, replace the APP sensor.
  1. With the DMM still connected to the 5-volt reference circuit, disconnect all other components connected to the 5-volt reference 3, one at a time.
  • If voltage changes when one of the above components is disconnected, replace the component.
  1. Test the 5-volt reference 3 circuits for a short to ground or a short to voltage.
  • If no problem was found in the 5-volt reference 3 circuit, replace the ECM.
 
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