How to Troubleshoot the A/T System

How to Check for DTCs with the Honda Diagnostic System (HDS)


When the powertrain control module (PCM) senses an abnormality in the input or output system, the D indicator (A) in the gauge control module (tach) (B) will usually blink.

 

When the Honda Diagnostic System (HDS) is connected to the data link connector (DLC) (A) (located behind the driver's dashboard lower cover) and the SCS mode is selected, it will indicate the diagnostic trouble code (DTC) when the ignition switch is turned ON (II) and the appropriate menu is selected.

 

If the D indicator or malfunction indicator lamp (MIL) has been reported on, or if a driveability problem is suspected, follow this procedure:

1.Connect the HDS to the DLC. (See the HDS user's manual for specific instructions.)

2.Turn the ignition switch ON (II), select A/T system, and observe the DTC in the DTCs MENU on the HDS screen.

3.Record all fuel and emissions DTCs, and A/T DTCs, and freeze data.

4.If there is a fuel and emissions DTC, first check the fuel and emissions system as indicated by the DTC (except for DTC P0700, DTC P0700 means there is one or more A/T DTCs, and no problems were detected in the fuel and emissions circuit of the PCM).

5.Clear the DTC and data.

6.Drive the vehicle for several minutes under the same conditions as those indicated by the freeze data, and then recheck for a DTC. If the A/T DTC returns, go to the DTC troubleshooting index. If the DTC does not return, there was an intermittent problem within the circuit. Make sure all pins and terminals in the circuit are tight.

Symptom Troubleshooting Versus DTC Troubleshooting


Some symptoms will not trigger diagnostic trouble codes (DTCs) or cause the D indicator to blink. If the malfunction indicator lamp (MIL) was reported ON or the D indicator has been blinking, check for DTCs. If the vehicle has an abnormal symptom, and there are no DTCs stored, go to the symptom troubleshooting index. Check the list of probable cause(s) for the symptom, in the sequence listed, until you find the problem.

How to Troubleshoot Circuits at the PCM


NOTE: The PCM overwrite data and monitors the EVAP system for up to 15 minutes after the ignition switch is turned OFF. Jumping the SCS line after turning the ignition switch OFF cancels this function. Disconnecting the PCM during this function, without jumping the SCS line first, can damage the PCM.

1.Turn the ignition switch OFF.

2.Connect the HDS to the DLC (A).

NOTE: If the HDS does not communicate with the PCM, troubleshoot the DLC circuit.

 

3.Jump the SCS line with the HDS.

4.Check for loose or poor connections at PCM connectors, and check for poor connections or loose terminals at the connectors in the circuit.

5.Troubleshoot a problem according to the DTC troubleshooting.
Inspect the circuit with a digital multitester (A) and a pin probe (B). When troubleshooting at the PCM connector (C), slide a suitable pin probe into the inspection port (D) at the PCM connector terminal side. Do not slide the probe into the PCM connector terminals (E).

 

Clear A/T DTCs Procedures


1.Connect the HDS to the DLC (A).

NOTE: If the HDS does not communicate with the PCM, troubleshoot the DLC circuit.

 

2.Turn the ignition switch ON (II).

3.Clear the DTC(s) on the HDS screen.

OBD Status


The OBD status shows the current system status of each DTC and all of the parameters. This function is used to see if the technician's repair was successfully finished. The results of diagnostic tests for the DTC are displayed as:

  • PASSED: On board diagnosis is successfully finished.
  • FAILED: On board diagnosis has finished but failed.
  • NOT COMPLETED: The on board diagnosis was running but is out of the enable conditions of the DTC.

How to End a Troubleshooting Session


This procedure must be done after any troubleshooting.

1.Reset the PCM with the HDS while the engine is stopped.

2.Turn the ignition switch OFF.

3.Turn the ignition switch ON (II), and wait for 30 seconds.

4.Turn the ignition switch OFF, and disconnect the HDS from the DLC.

5.Do the PCM idle learn procedure.

6.Start the engine in the P or N position, and warm it to normal operating temperature (the radiator fan comes on).

7.To verify that the problem is repaired, test-drive the vehicle for several minutes at speeds over 50 km/h (30 mph) or in freeze data range.

PCM Updating and Substitution for Testing


Special Tools Required
Honda interface module (HIM) (  EQS05A35570)



Use this procedure when you have to substitute a known-good PCM in a troubleshooting procedure. Update the PCM only if the PCM does not already have the latest software loaded.

NOTE: Do not turn the ignition switch OFF while updating the PCM. If you turn the ignition switch OFF before completion, the PCM can be damaged.

How to Update the PCM


NOTE:
  • To ensure the latest program is installed, do a PCM update whenever the PCM is substituted or replaced.
  • You cannot update a PCM with the program it already has. It will only accept a new program.
  • Before you update the PCM, make sure the vehicle's battery is fully charged.
  • To prevent PCM damage, do not operate anything electrical (audio system, brakes, A/C, power windows, moonroof, or door locks) during the update.
  • If you need to diagnose the Honda interface module (HIM) because the HIM's red (#3) light came on or was flashing during the update, leave the ignition switch in the ON (II) position when you disconnect the HIM from the data link connector (DLC). This will prevent PCM damage.

1.Turn the ignition switch ON (II). Do not start the engine.

2.Connect the HDS to the DLC (A).

NOTE: If the HDS does not communicate with the PCM, troubleshoot the DLC circuit.

 

3.Select the INSPECTION MENU with the HDS.

4.Do the TP LEARNING CHECK in the ETCS TEST.

5.If the HDS does not have the update function, disconnect the HDS from the DLC, and connect the Honda interface module (HIM) to the DLC.

6.Do the PCM update procedure as described on the HIM label and in the PCM update system.

7.Do the PCM idle learn procedure.

8.Clear the CKP pattern with the HDS while the engine stopped.

How to Substitute the PCM


1.Connect the HDS to the DLC (A).

NOTE: If the HDS does not communicate with the PCM, troubleshoot the DLC circuit.

 

2.Jump the SCS line with the HDS.

3.Remove the PCM cover (A).

 

4.Disconnect PCM connectors A, B, and C.

NOTE: PCM connectors A, B, and C have symbols (A=¨, B=[utri], C=¡) embossed on them for identification.

5.Remove the mounting bolts, and remove the PCM.

6.Install a known-good PCM in the reverse order of removal.

7.Open the SCS with the HDS.

8.Turn the ignition switch ON (II).

NOTE: If DTC P0630 ‘‘VIN not Programmed or Mismatch'' will be stored because the VIN has not been programmed into the PCM; ignore it, and continue this procedure.

9.Input the VIN to the PCM with the HDS.

10.Rewrite the immobilizer code with the PCM replacement procedure in the HDS; it allows you to start the engine.

11.Reset the PCM with the HDS while the engine is stopped.

12.Select INSPECTION MENU with the HDS.

13.Do the TP POSITION CHECK in the ETCS TEST.

14.Do the PCM idle learn procedure.