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Home >> Mazda >> 2006 >> MX-5 Miata Base >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic [Engine Control System] >> DTC P2101 >> Diagnostic Procedure
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Diagnostic Procedure

DTC P2101 DIAGNOSTIC PROCEDURE TABLE

STEP INSPECTION ACTION
1 VERIFY FREEZE FRAME DATA HAS BEEN RECORDED 
  • Has FREEZE FRAME DATA been recorded?
 Yes Go to the next step.
No Record the FREEZE FRAME DATA on the repair order, then go to the next step.
2 VERIFY RELATED REPAIR INFORMATION AVAILABILITY 
  • Verify related Service Bulletins and/or on-line repair information availability.
  • Is any related repair information available?
 Yes Perform repair or diagnosis according to the available repair information.
  • If the vehicle is not repaired, go to the next step.
No Go to the next step.
3 VERIFY RELATED PENDING AND STORED DTCS 
  • Turn the ignition switch off, then to the ON position (Engine off).
  • Verify the pending and stored DTCs using the WDS or equivalent.
  • Is any DTC present?
 Yes Go to the applicable DTC inspection.
(See DTC TABLE  .)
No Go to the next step.
4 IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA. 
  • Is DTC P2101 on FREEZE FRAME DATA?
 Yes Go to the next step.
No Go to the troubleshooting procedures for DTC on OBD-II FREEZE FRAME DATA  .
5 INSPECT PCM CONNECTOR FOR POOR CONNECTION 
  • Turn the ignition switch off.
  • Disconnect the PCM connector.
  • Inspect for poor connection (such as damaged, pulled out terminals, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the terminal, then go to Step 22.
No Go to the next step.
6 INSPECT MAIN RELAY OUTPUT VOLTAGE 
  • Turn the ignition switch off.
  • Connect the PCM connector.
  • Turn the ignition switch to the ON position (Engine off).
  • Measure the voltage between PCM terminal 1 BE and body ground.
  • Is the voltage B+  ?
 Yes Go to Step 13.
No Go to the next step.
7 INSPECT MAIN RELAY CONNECTOR FOR POOR CONNECTION 
  • Turn the ignition switch off.
  • Disconnect the main relay.
  • Inspect for poor connection (such as damaged, pulled out terminals, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the terminal, then go to Step 22.
No Go to the next step.
8 INSPECT POWER SUPPLY OF MAIN RELAY 
  • Turn the ignition switch to the ON position (Engine off).
  • Measure the voltage between main relay and body ground.
  • Is the voltage B+  ?
 Yes Go to the next step.
No Repair or replace the wiring harness for an open circuit, then go to Step 22.
9 INSPECT POWER SUPPLY FOR CONTROL CIRCUIT OF MAIN RELAY 
  • Turn the ignition switch to the ON position (Engine off).
  • Measure the voltage between main relay and body ground.
  • Is the voltage B+  ?
 Yes Go to the next step.
No Go to Step 22.
10 INSPECT MAIN RELAY  Yes Go to the next step.
No Replace the main relay, then go to Step 22.
11 INSPECT POWER CIRCUIT FOR OPEN CIRCUIT 
  • Turn the ignition switch off.
  • Disconnect the main relay and the PCM connector.
  • Inspect for continuity between main relay and PCM terminal 1BE (wiring harness-side).
  • Is there continuity?
 Yes Go to the next step.
No Repair or replace the wiring harness for an open circuit, then go to Step 22.
12 INSPECT CONTROL CIRCUIT FOR OPEN CIRCUIT 
  • Inspect for continuity between main relay and PCM terminal 1Q (wiring harness-side).
  • Is there continuity?
 Yes Repair or replace the wiring harness for an open circuit, then go to Step 22.
No Go to Step 22.
13 INSPECT DRIVE-BY-WIRE RELAY OUTPUT VOLTAGE 
  • Turn the ignition switch to the ON position (Engine off).
  • Measure the voltage between PCM terminal 1BF (wiring harness-side) and body ground.
  • Is the voltage B+  ?
 Yes Go to Step 20.
No Go to the next step.
14 INSPECT DRIVE-BY-WIRE RELAY CONNECTOR FOR POOR CONNECTION 
  • Turn the ignition switch off.
  • Disconnect the drive-by-wire relay.
  • Inspect the drive-by-wire relay connector (wiring harness-side) for poor connection (such as damaged, pulled out terminals, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the terminal, then go to Step 22.
No Go to the next step.
15 INSPECT POWER SUPPLY OF DRIVE-BY-WIRE RELAY 
  • Turn the ignition switch to the ON position (Engine off).
  • Measure the voltage between drive-by-wire relay terminal C (wiring harness-side) and body ground.
 Yes Go to the next step.
No Repair or replace the wiring harness for an open circuit, then go to Step 22.
16 INSPECT POWER SUPPLY FOR CONTROL CIRCUIT OF DRIVE-BY-WIRE RELAY 
  • Turn the ignition switch to the ON position (Engine off).
  • Measure the voltage between the drive-by-wire relay terminal A (wiring harness-side) and body ground.
  • Is the voltage B+  ?
 Yes Go to the next step.
No Repair or replace the wiring harness for an open circuit between drive-by-wire relay terminal A and main relay terminal C, then go to Step 22.
17 INSPECT DRIVE-BY-WIRE RELAY 
  • Inspect the drive-by-wire relay.

    (See RELAY INSPECTION .)

  • Is the drive-by-wire relay normal?
 Yes Go to the next step.
No Replace the drive-by-wire relay, then go to Step 22.
18 INSPECT POWER CIRCUIT FOR OPEN CIRCUIT 
  • Turn the ignition switch off.
  • Inspect for continuity between drive-by-wire relay terminal D (wiring harness-side) and PCM terminal 1 BF (wiring harness-side).
  • Is there continuity?
 Yes Go to the next step.
No Repair or replace the wiring harness for an open circuit, then go to Step 22.
19 INSPECT CONTROL CIRCUIT FOR OPEN CIRCUIT 
  • Inspect for continuity between drive-by-wire relay E (wiring harness-side) and PCM terminal 1BE (wiring harness-side).
 Yes Go to the next step.
No Repair or replace the wiring harness for an open circuit, then go to Step 22.
20 INSPECT THROTTLE POSITION SENSOR NO.1 OUTPUT VOLTAGE 
  • Turn the ignition switch off.
  • Connect the PCM connector.
  • Turn the ignition switch to the ON position (Engine off).
  • Inspect the voltage between PCM terminal 2AK and body ground.
  • Is the voltage 0.40-0.60 V  ?
 Yes Go to the next step.
No Inspect throttle position sensor No.1 and the related circuits and terminals.
(See THROTTLE POSITION (TP) SENSOR INSPECTION .) Repair or replace if necessary, then go to Step 22.
21 INSPECT THROTTLE POSITION SENSOR NO.2 OUTPUT VOLTAGE 
  • Turn the ignition switch to the ON position (Engine off).
  • Inspect the voltage between PCM terminal 2AL and body ground.
  • Is the voltage 4.40-4.60 V  ?
 Yes Go to the next step.
No Check throttle position sensor No.2 and the related circuits and terminals.
(See THROTTLE POSITION (TP) SENSOR INSPECTION .) Repair or replace if necessary, then go to the next step.
22 VERIFY TROUBLESHOOTING OF DTC P2101 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Turn the ignition switch to the ON position (Engine off).
  • Clear the DTC from the PCM memory using the WDS or equivalent.
  • Start the engine and idle it.
  • Turn the ignition switch off, then to the ON position (Engine off).
  • Is the same DTC present?
 Yes Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION .)
No Go to the next step.
23 VERIFY AFTER REPAIR PROCEDURE  Yes Go to the applicable DTC inspection.
(See DTC TABLE  .)
No Troubleshooting completed.
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