P1330

DTC P1330 Spark Timing Adjust Malfunction

General Description

The ECM computes ignition timing in response to the signals from several sensors. The timing is fixed during the start up phase. However, when the engine has been started and the vehicle is driven away, the ECM computes the optimum timing base on the engine speed, load and temperature. The ignition timing is fixed BTDC 5 and DTC P1330 is set when connecting ignition control terminal of Data Link Connector and ground. If you disconnect Ignition control terminal of Data Link Connector and ground, the DTC is erased automatically. Make sure the check for short circuit to ground between Ignition control terminal of Data Link Connector and chassis ground when DTC is set.

DTC Description

If the ignition control terminal of the Data Link Connector is grounded, the ECM determines that a fault exists and a DTC is stored.




Detecting Condition

Terminal and Connector Inspection

1. Many malfunctions in the electrical system are caused by poor harness and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.

2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration or damage.

3. Has a problem been found?

YES - Repair as necessary and go to "Verification of vehicle repair" procedure.

NO - Go to "Control circuit inspection" procedure.

Control Circuit Inspection

1. Check for open in harness
(1) Ignition "OFF"
(2) Disconnect Data link connector and ECM connector.




(3) Measure resistance between terminal "19" of Data link connector and terminal "A23" of ECM harness connector.

Specification: approx. below 1 Ohm

(4) Is the measured resistance within specifications?

YES -Go to "Check for short to ground in harness" as below.

NO - Check open in harness between Data link connector and ECM connector. Repair or replace as necessary and the go to "Verification of vehicle repair" procedure.

2. Check for short to ground in harness.
(1) Ignition "OFF"
(2) Disconnect Data link connector and ECM connector.





(3) Measure resistance between terminal "19" of Data link connector and chassis ground.

Specification: infinite

(4) Is the measured resistance within specifications?

YES - Substitute with known good ECM and check fro proper operation. If the problem is corrected, replace ECM and go to "Verification of vehicle repair" procedure.

NO - Check for short to ground in harness. Repair or replace as necessary and then go to "Verification of vehicle repair" procedure.

Verification of Vehicle Repair

1. Monitor and record the Freeze Frame Data for the DTC which has been diagnosed.

2. Using a Scantool, clear the DTCs.

3. Operate the vehicle within conditions noted in the freeze frame data or enable conditions.

4. Monitor that all readiness test have been verified as "Complete"

5. Are any DTCs present?

YES -Go to applicable troubleshooting procedure.

NO -System is performing to specification at this time.