Code 12, 13 - Rpm Signal
Code 12 is caused by loss of "G2", "G1", or "NE" signal (3S-GTE), or "G" or "NE" signal (all others), from distributor to ECU for at least 2 seconds after starter signal is received at ECU. Check distributor and ignition system components. See I - SYS/COMP TESTS article in the ENGINE PERFORMANCE Section. Ensure starter signal exists at ECU. See MR2 TEST NO. 10 OR CODE 43.
Code 13 is caused by loss of "NE" signal from distributor to ECU when engine RPM exceeds 1000 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.