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.
Key On Engine Running (KOER) Self-Test Procedure
1998 Mazda 626 LX L4-2.0L DOHCSECTION Key On Engine Running (KOER) Self-Test Procedure
KEY ON ENGINE RUNNING SELF-TEST PROCEDURE
NOTE:
- Make sure the A/C switch is OFF during KOER Self-Test. If the A/C switch is ON during this test, DTC P1464 will be indicated on the NGS tester.
- The brake pedal must be depressed and released after KOER Self-Test is initiated. If not performed, DTC P1703 will be indicated on the NGS tester.
- The steering wheel must be turned to the right and left after KOER Self-Test is initiated. If not performed, DTC P1650 will be indicated on the NGS tester.
- Start the engine and bring up to normal operating temperature before running the KOER Self-Test.
1. Perform the "New Generation Star (NGS) tester hook-up procedure".
2. Perform the "Reading DTC Procedure".
3. Move the cursor to KOER ON-DEMAND SELF-TEST. Press the trigger to enter this selection.
4. Start engine and bring up to normal operating temperature. Press START.
5. Follow operating instruction from the menu and perform Brake On/Off (BOO), O/D OFF switch and PSP cycling test, if equipped.
6. Note any KOER DTCs.
7. Press CANCEL several times to return to the main menu.
NOTE:
- Make sure the A/C switch is OFF during KOER Self-Test. If the A/C switch is ON during this test, DTC P1464 will be indicated on the NGS tester.
- The brake pedal must be depressed and released after KOER Self-Test is initiated. If not performed, DTC P1703 will be indicated on the NGS tester.
- The steering wheel must be turned to the right and left after KOER Self-Test is initiated. If not performed, DTC P1650 will be indicated on the NGS tester.
- Start the engine and bring up to normal operating temperature before running the KOER Self-Test.
1. Perform the "New Generation Star (NGS) tester hook-up procedure".
2. Perform the "Reading DTC Procedure".
3. Move the cursor to KOER ON-DEMAND SELF-TEST. Press the trigger to enter this selection.
4. Start engine and bring up to normal operating temperature. Press START.
5. Follow operating instruction from the menu and perform Brake On/Off (BOO), O/D OFF switch and PSP cycling test, if equipped.
6. Note any KOER DTCs.
7. Press CANCEL several times to return to the main menu.
RENDER: 1.0x
NO RELATED
Recommended Tools & Savings
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
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.