Acura TSX / Honda Accord CL. Manual — part 505

1. Connect the Honda Diagnostic System (HDS) to the data link connector (DLC) (see step 2 of

GENERAL TROUBLESHOOTING INFORMATION ), and check for DTC's. If a DTC is present,
diagnose and repair the cause before inspecting the ignition timing.

2. Start the engine. Hold the engine at 3,000 RPM with no load (in Neutral) until the radiator fan comes on,

then let it idle.

3. Check the idle speed (see IDLE SPEED INSPECTION ).

4. Follow the tester's prompts to get the tester in the "SCS" mode (see the operator's manual).

5. Free the service loop from the wire harness, then connect the timing light to the service loop.

Fig. 3: Aiming The Timing Light Toward The Pointer On The Cam Chain Case

2004 Acura TSX

2004 Engines Ignition System - TSX

6. Aim the light toward the pointer (A) on the cam chain case. Check the ignition timing under no load

condition: headlights, blower fan, rear window defogger, and air conditioner are not operating.

Ignition Timing:

M/T: 8° +/- 2° BTDC (RED mark (B)) at idle in Neutral

A/T: 8° +/- 2° BTDC (RED mark (B)) at idle in Park or Neutral

Fig. 4: Identifying Timing Marks

7. If the ignition timing differs from the specification, check cam timing. If cam timing is OK, update the

engine control module (ECM)/powertrain control module (PCM) if it does not have the latest software, or
substitute a known-good ECM/PCM (see ECM/PCM UPDATING AND SUBSTITUTION FOR
TESTING ), then recheck. If the system work properly, and the ECM/PCM was substituted, replace the
original ECM/PCM (see HOW TO REMOVE THE ECM/PCM FOR TESTING ).

8. Disconnect the HDS and the timing light.

9. Secure the service loop to the wire harness with wire ties.

2004 Acura TSX

2004 Engines Ignition System - TSX

IGNITION COIL REMOVAL/INSTALLATION

1. Remove the ignition coil cover (A), disconnect the ignition coil connectors (B), then remove the ignition

coils (C).

Fig. 5: Removing The Ignition Coil Cover, Disconnecting The Ignition Coil Connectors, &
Removing The Ignition Coils

2. Install the ignition coils in the reverse order of removal.

IGNITION COIL RELAY CIRCUIT TROUBLESHOOTING

1. Check the No. 2 (30A) fuse in the under-dash fuse/relay box.

Is the fuse OK?

YES: Go to step 2.

2004 Acura TSX

2004 Engines Ignition System - TSX

NO: Replace the fuse.

2. Remove the ignition coil relay from the under-dash fuse/relay box and test it (see POWER RELAY

TEST ).

Is the relay OK?

YES: Go to step 3.

NO: Replace the ignition coil relay.

3. Measure the voltage between ignition coil relay 4P socket terminal No. 1 and body ground, then terminal

No. 4 and body ground.

Is there battery voltage?

YES: Go to step 4.

NO: Replace the under-dash fuse/relay box.

2004 Acura TSX

2004 Engines Ignition System - TSX