LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Mazda >> 2010 >> 5 Touring, 2.3 L >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic [Engine Control System L3] >> DTC P2177 >> Diagnostic procedure
July 1: So it begins. Don't worry, this is not in the correct legal jurisdiction!

Diagnostic procedure

DTC P2177 [L3] DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA (MODE 2) 
  • Is DTC P2177 on FREEZE FRAME DATA (Mode 2)?
Yes Go to the next step.
No Go to troubleshooting for DTC on FREEZE FRAME DATA (Mode 2).
(See DTC TABLE .)
2 VERIFY FREEZE FRAME DATA (MODE 12) HAVE BEEN RECORDED 
  • Have FREEZE FRAME DATA (Mode 12) been recorded?
Yes Go to the next step.
No Record the FREEZE FRAME DATA (Mode 12) on the repair order, then go to the next step.
3 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.
4 VERIFY RELATED PENDING CODE OR STORED DTCS 
  • Turn the ignition switch off, then to the ON position (Engine off).
  • Verify related pending code or stored DTCs.
  • Is other DTC present?
Yes If misfire DTC is present, go to Step 8.
If other DTC is present, go to the applicable DTC inspection.
(See DTC TABLE .)
No If drive ability concern is present, go to Step 8.
If not, go to the next step.
5 VERIFY CURRENT INPUT SIGNAL STATUS (IGNITION SWITCH TO THE ON POSITION/IDLE) 
  • Access PCM PIDs APP1, APP2, ECT, MAF, TP REL and VSS using M-MDS.
  • Is there any signal that is far out of specification when the ignition switch is at the ON position and the engine runs?
Yes Inspect the suspected circuit.
  • If the inspection results are normal:
    • Go to the next step.
  • If the inspection results are not normal:
    • Repair or replace the malfunctioning part according to the inspection results, then go to Step 17.
No Go to the next step.
6 VERIFY CURRENT INPUT SIGNAL STATUS UNDER TROUBLE CONDITION 
CAUTION:
  • While performing this step, always operate the vehicle in a safe and lawful manner.
  • When the M-MDS is used to observe monitor system status while driving, be sure to have another technician with you, or record the data in the M-MDS using the PID/DATA MONITOR AND RECORD capturing function and inspect later.

  • Inspect the same PIDs as Step 5 while simulating FREEZE FRAME DATA (Mode 2) condition.
  • Is there any signal which causes drastic changes?
Yes Inspect the suspected circuit.
  • If the inspection results are normal:
    • Go to the next step.
  • If the inspection results are not normal:
    • Repair or replace the malfunctioning part according to the inspection results, then go to Step 17.
No Go to the next step.
7 INSPECT A/F SENSOR HEATER 
Yes Replace the A/F sensor, then go to Step 20.
(See EXHAUST SYSTEM REMOVAL/INSTALLATION .)
No Go to the next step.
8 VERIFY CURRENT INPUT SIGNAL STATUS OF A/F SENSOR 
Yes Go to the next step.
No Go to Step 11.
9 INSPECT INSTALLATION OF A/F SENSOR 
  • Inspect if the A/F sensor is loosely installed.
  • Is the A/F sensor installed securely?
Yes Go to the next step.
No Retighten the A/F sensor, then go to Step 20.
(See EXHAUST SYSTEM REMOVAL/INSTALLATION .)
10 INSPECT EXHAUST GAS LEAKAGE 
  • Visually inspect for the exhaust gas leakage between exhaust manifold and A/F sensor.
  • Is there any malfunction?
Yes Repair or replace the malfunctioning part according to the inspection results, then go to Step 20.
No Replace the A/F sensor, then go to Step 20.
(See AIR FUEL RATIO (A/F) SENSOR, HEATED OXYGEN SENSOR (HO2S) REMOVAL/INSTALLATION .)
11 VERIFY CURRENT INPUT SIGNAL STATUS OF MAF SENSOR 
  • Start the engine.
  • Access the PCM PID MAF using the M-MDS.
  • Verify that the MAF PID changes quickly according to engine speed.
  • Is the PID normal?
Yes Go to Step 13.
No Go to the next step.
12 INSPECT FOR EXCESSIVE AIR SUCTION OF INTAKE AIR SYSTEM 
  • Visually inspect for loosen, cracks or damages hoses on intake air system.
    NOTE:
    • Engine speed may change when rust penetrating agent is splayed on the air suction area.
  • Is there any malfunction?
Yes Repair or replace source of air suction, then go to Step 20.
No Replace MAF/IAT sensor, then go to Step 20.
13 INSPECT PURGE SOLENOID OPERATION 
Yes Go to Step 16.
No Repair or replace the malfunctioning part according to inspection result, then go to Step 20.
14 INSPECT FUEL LINE PRESSURE 
Yes Go to Step 16.
No If the fuel pressure is too high, replace fuel pump unit, then go to Step 20.
If the fuel line pressure is low, go to the next step.
15 INSPECT FUEL LINE FROM FUEL PUMP TO FUEL DISTRIBUTOR 
  • Visually inspect fuel line for any leakage.
  • Is fuel leakage found?
Yes Replace suspected fuel line, then go to Step 20.
No Inspect for foreign materials or stain inside fuel filter (low-pressure).
If for foreign materials or stain inside fuel filter (low-pressure), clean of fuel tank and filter.
Then go to Step 20.
16 INSPECT IGNITION SYSTEM 
Yes Go to the next step.
No Repair or replace the malfunctioning part according to spark test result, then go to Step 20.
17 INSPECT ENGINE COMPRESSION 
Yes Go to the next step.
No Implement the engine overhaul for repairs, then go to Step 20.
18 INSPECT VARIABLE VALVE TIMING CONTROL SYSTEM OPERATION 
Yes Go to the next step.
No Repair or replace the malfunctioning part according to inspection results, then go to Step 20.
19 INSPECT FUEL INJECTOR OPERATION 
Yes Go to the next step.
No Repair or replace malfunctioning part according to inspection result, then go to the next step.
20 VERIFY TROUBLESHOOTING OF DTC P2177 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Clear the DTC from the PCM memory using the M-MDS.

    (See AFTER REPAIR PROCEDURE .)

  • Perform the KOER self test.

    (See KOEO/KOER SELF TEST .)

  • Is the PENDING CODE for this DTC present?
Yes Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION .)
No Go to the next step.
21 VERIFY AFTER REPAIR PROCEDURE 
Yes Go to the applicable DTC inspection.
(See DTC TABLE .)
No Troubleshooting completed.