3.
Monitor "MAPS" parameter on scantool.
The amount of intake air flow must be inputted to PCM in order to determine the fuel injection quantity. MAPS(Manifold Absolute Pressure) calculates the amount of air indirectly as measuring the pressure inside of intake manifold. This mechanism is alsl called Speed-Density Type.
MAPS transfers analog output signal which is proportional to the change of intake manifold pressure, then, with this signal and RPM, PCM calculates the amount of intake air flow.
MAPS is mounted on surge tank to measure the pressure inside of intake manifold, and it consists of a piezo electric element and hybrid IC which amplifies output signal from the element. A piezo electric element is a sort of a diaphragm using piezo electric effect. One side of the diaphragm is surrounded with vacuum chamber while intake pressure is applied to the other side. Thus, signals are output by the transformation of diagphragm according to the change of pressure inside of intake manifold.
If intake manifold pressure is lower than the minimum threshold value or higher than the maximum threshold value according to RPM and TPS under normal TPS signal input condition, ECM sets DTC P0106.
Item | Detecting Condition | Possible Cause |
DTC Strategy | ● Rationality check | ● Poor connection ● MAPS ● ECM |
Enable Conditions | ● No TPS error detected | |
Threshold Value | ● Intake manifold pressure 〉 max. Threshold f(Eng. Speed, TPS) ● Intake manifold pressure 〈 min. Threshold f(Eng. Speed, TPS) | |
Diagnostic Time | ● 5 sec | |
MIL | ● ON |
Connect scantool to DLC(Data Link Cable).
Warm up the engine to normal operating temperature.
Monitor "MAPS" parameter on scantool.
Is the "MAPS" parameter displayed correctly?
▶ Fault is intermittent caused by poor contact in the sensor’s and/or ECM’s connector or was repaired and ECM memory was not cleared. Thoroughly check connectors for looseness, poorconnection, ending, corrosion, contamination, deterioration, or damage. Repair or replace asnecessary and go to "Verification of Vehicle Repair" procedure.
▶ Go to "Terminal and Connector Inspection" procedure.
Many malfunctions in the electrical system are caused by poor harness and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
Has a problem been found?
▶ Repair as necessary and go to "Verification of vehicle Repair" procedure.
▶ Go to " Voltage Inspection " procedure.
Check MAPS performance.
IG "OFF".
Connnect CH A probe to terminal 1 of MAPS and CH B probe to terminal 1 of TPS connector.
Warm up the engine to normal operating temperature.
Measure signal waveform of MAPS and TPS together by stepping on and off the accellerator padel.
Is the measured signal waveform(Comparison response of TPS with MAPS) O.K?
▶ Go to "Check ECM" as follows.
▶ Substitute with a known - good MAPS and check for proper operation.
▶ If the problem is corrected, replace MAPS and go to "Verification of Vehicle Repair" procedure.
Check ECM.
IG "OFF" and disconnect MAPS connector.
Connect scantool and Key "ON".
Select simulation function on scantool.
Simulate voltage at terminal 1 of MAPS signal connector.
Does the signal value of MAPS change according to simulation voltage?
▶ Thoroughly check connectors for looseness, poor connection, bending, corrosion,contamination, deterioration, or damage. Repair or replace as necessary and go to "Verificationof Vehicle Repair" procedure.
▶ Substitute with a known - good ECM and check for proper operation.
▶ If the problem is corrected, replace ECM and go to "Verification of Vehicle Repair" procedure.
After a repair, it is essential to verify that the fault has been corrected.
Connect scan tool and select "Diagnostic Trouble Codes(DTCs)" mode.
Clear the DTCs and Operate the vehicle within DTC Enable conditions in General information.
Are any DTCs present ?
▶ Go to the applicable troubleshooting procedure.
▶ System is performing to specification at this time.
