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 ECM for at least 2 seconds after starter signal is received at ECM. Check distributor and ignition system components. See the article SYSTEM/COMPONENT TESTS in this section. Ensure starter signal exists at ECM. See MR2 TEST NO. 10 OR CODE 43.
Code 13 is caused by loss of "NE" signal from distributor to ECM when engine RPM exceeds 1000 RPM. Check distributor and ignition system components. See SYSTEM/COMPONENT TESTS article in this section.
NOTE:
Diagnostic chart for Code 12 or 13 is not available from manufacturer.