Code 12, 13 - Rpm Signal
Code 12 is caused by loss of "NE" signal from distributor to ECU for at least 2 seconds after starter signal (STA) is received at ECU. Check distributor and ignition system components. See See I - SYS/COMP TESTS article in the ENGINE PERFORMANCE Section. Ensure starter signal (STA) exists at ECU. See TEST NO. 7 OR CODE 43.
Code 13 is caused by loss of "NE" signal from distributor to ECU when engine RPM exceeds 1500 RPM. Check distributor and ignition system components. See I - SYS/COMP TESTS article in the ENGINE PERFORMANCE Section.
NOTE:
Diagnostic chart for Code 12 or 13 is not available from manufacturer.