October 30: LEMON manuals on a temporary server, it is slow and having issues, download the manuals you need! Later in November we will switch back to the fast server.
Engine Controls - Tests W/Codes Expand All (for easy ctrl-f) Collapse All Introduction Self-Diagnostic System Summary Diagnostic Code Charts Notes Diagnostic Circuit Check Chart A-1, Won't Flash Code 12, No Check Engine Light Chart A-2, No ALDL Data Or Won't Flash Code 12, Check Engine Light On At All Times CODE 13, HEATED OXYGEN (O2) SENSOR CKT, OPEN CKT (GSi) CODE 13, NON-HEATED OXYGEN SENSOR CKT, OPEN CKT (EXCEPT GSi) Code 14, Coolant Temp Sensor (Cts) CKT High Temp Indicated Code 14, Coolant Temp Sensor (Cts) CKT, Low Temp Indicated Code 21, Throttle Position Sensor CKT, Signal Voltage High Code 21, Throttle Position Sensor CKT, Signal Voltage Low Code 23, Intake Air Temp (IAT) Sensor CKT, Low Temp Indicated Code 23, Intake Air Temp Sensor CKT, High Temp Indicated Code 24, Vehicle Speed Sensor (VSS) Circuit Code 32, EGR System Error (CALIF. Only) Code 33, Map Sensor Circuit, Signal Voltage High - Low Vacuum Code 33, Map Sensor Circuit, Signal Voltage Low - High Vacuum Code 42, Electronic Spark Timing (Est) Circuit CODE 44, HEATED O2 SENSOR CKT, LEAN EXHAUST INDICATED (GSi) CODE 44, NON-HEATED O2 SENSOR CKT, LEAN EXHAUST INDICATED (EXCEPT GSi) CODE 45, HEATED O2 SENSOR CKT, RICH EXHAUST INDICATED (GSi) CODE 45, NON-HEATED O2 SENSOR CKT, RICH EXHAUST INDICATED (EXCEPT GSi) Code 51, ECM Failure, ECM Failed Or Prom Failure