Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2012 Honda Fit Base, Standard TransFACTORY OEM SERVICE PROCEDURE
Special Tools Required
- Honda diagnostic system (HDS) tablet tester
- Honda interface module (HIM) and an iN workstation with the latest HDS software version
- HDS pocket tester
- GNA600 and an iN workstation with the latest HDS software version
Any one of the above updating tools can be used.
NOTE:
Make sure the HDS/iN workstation has the latest HDS software version.
- Connect the HDS to the data link connector (DLC) (A) located under the driver's side of the dashboard.
- Turn the ignition switch to ON (II).
- Make sure the HDS communicates with the ECM/PCM and other vehicle systems. If it doesn't, go to DLC CIRCUIT TROUBLESHOOTING
. If you are returning from the DLC circuit troubleshooting, skip steps 4 through 9, 19 through 24, and 27 through 29, and do these procedures after replacing the ECM/PCM:
- Replace the engine oil (see ENGINE OIL LEVEL CHECK ) and the engine oil filter (see ENGINE OIL FILTER REPLACEMENT ).
- Replace the ATF (A/T) (see ATF REPLACEMENT ).
- Clean the throttle body (see THROTTLE BODY CLEANING ).
- Select the PGM-FI system with the HDS.
- Select the INSPECTION MENU with the HDS.
- Select the ETCS TEST, then select the TP POSITION CHECK, and follow the screen prompts.NOTE: If the TP POSITION CHECK indicates FAILED, continue with this procedure.
- Select the REPLACE ECM/PCM MENU, then select READ DATA, and follow the screen prompts.NOTE:
- Doing this step copies (READS) the engine oil life data from the original ECM/PCM so you can later download (WRITES) it into the new ECM/PCM.
- If READ DATA indicates FAILED, continue with this procedure.
- A/T: Select the A/T system with the HDS.
- A/T: Select the REPLACE TCM/PCM MENU, then READ DATA, and follow the screen prompts.NOTE:
- A/T: Doing this step copies (READS) the ATF life data from the original PCM so you can later download (WRITES) it into the new PCM.
- A/T: If READ DATA indicates FAILED, continue with this procedure.
- Jump the SCS line with the HDS.
- Turn the ignition switch to LOCK (0).
- Remove the ECM/PCM cover (A).
- Remove the battery holder (B), and reposition the battery away from the ECM/PCM.NOTE: Do not disconnect the battery terminals.
- Remove the bolts (D), and loosen the bolt (E).
- Disconnect ECM/PCM connectors A, B, and C, then remove the ECM/PCM (F).NOTE: ECM/PCM connectors A, B, and C have symbols (A=□, B=Δ, C=◦) embossed on them for identification.
- Install a known-good ECM/PCM in the reverse order of removal.
- Turn the ignition switch to ON (II).
- Manually input the VIN to the ECM/PCM with the HDS.NOTE: DTC P0630 (VIN Not Programmed or Mismatch) may be stored because the VIN has not been programmed into the ECM/PCM; ignore it, and continue this procedure.
- If the READ DATA (engine oil life) failed in step 7, go to step 22 (A/T) or step 25 (M/T). Otherwise, go to step 20.
- Select the PGM-FI system with the HDS.
- Select the REPLACE ECM/PCM MENU, then WRITE DATA, and follow the screen prompts.NOTE: If the WRITE DATA indicates FAILED, continue with this procedure.
- A/T: If the READ DATA (ATF life) failed in step 8, go to step 25. Otherwise go to step 23.
- A/T: Select the A/T SYSTEM with the HDS.
- A/T: Select the REPLACE ECM/PCM MENU, then WRITE DATA, and follow the screen prompts.NOTE: A/T: If the WRITE DATA indicates FAILED, continue with this procedure.
- Select IMMOBI system with the HDS.
- Enter the immobilizer code that you got from the iN, or use the ECM/PCM replacement procedure in the HDS; it allows you to start the engine.
- If the TP POSITION CHECK failed in step 6 clean the throttle body (see THROTTLE BODY CLEANING ), then go to step 28.
- If the READ DATA failed in step 7 or the WRITE DATA failed in step 21, replace the engine oil (see ENGINE OIL LEVEL CHECK ) and the engine oil filter (see ENGINE OIL FILTER REPLACEMENT ), then go to step 29 (A/T) or step 30 (M/T).
- If the READ DATA failed in step 9 or the WRITE DATA failed in step 24, replace the ATF (see ATF REPLACEMENT ), then go to step 30.
- Select the PGM-FI system, and reset the ECM/PCM with the HDS.
- Update the ECM/PCM if it does not have the latest software (see ECM/PCM UPDATE ).
- Do ECM/PCM IDLE LEARN PROCEDURE .
- Do the CKP pattern learn procedure (see CKP PATTERN CLEAR/CKP PATTERN LEARN ).
Factory Service Tools
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
