12 Initiation of diagnosis. n/a
13 Oxygen sensor Open circuit
14 Coolant temperature sensor Voltage low
15 Coolant temperature sensor Voltage high
16 Knock sensor signal circuit No change in voltage
19 Incorrect Revs per Minute (RPM) signal (crankshaft sensor) Incorrect signal, check sensor
21 Throttle position sensor (TPS) Voltage high
22 Throttle position sensor (TPS) Voltage low
23 Knock control module signal Out of range
24 Vehicle speed signal (VSS) No signal
25 Injector valve 1 Voltage high
26 Injector valve 2 Voltage high
27 Injector valve 3 Voltage high
28 Injector valve 4 Voltage high
37 Check light (fault code lamp) Voltage low
38 Oxygen sensor circuit Voltage high
39 Oxygen sensor circuit Voltage low
44 Oxygen sensor Lean exhaust (weak mixture)
45 Oxygen sensor Rich exhaust (rich mixture)
48 Battery Voltage low
49 Battery Voltage high
52 Check light (fault code lamp) Voltage high
53 Fuel pump relay Voltage low
54 Fuel pump relay Voltage high
55 Engine Control Unit (ECU) faulty Check chassis earth and ECU connector.
56 Idle air control Voltage high
57 Idle air control Voltage low
61 Fuel tank vent valve Voltage low
62 Fuel tank vent valve Voltage high
69 Intake air temperature sensor Voltage low
71 Intake air temperature sensor Voltage high
73 Mass air flow temperature Voltage low
74 Mass air flow temperature Voltage high
75 Torque control (automatic) Voltage low
76 Torque control (automatic) Continuous signal, ignition retard long
81 Injector valve 1 Voltage low. Injector short circuit to ground.
82 Injector valve 2 Voltage low. Injector short circuit to ground.
83 Injector valve 3 Voltage low. Injector short circuit to ground.
84 Injector valve 4 Voltage low. Injector short circuit to ground.
87 Air Conditioning (A/C) cut-off relay Voltage low
88 Air Conditioning (A/C) cut-off relay Voltage high 
91 Oxygen sensor heater Voltage high
92 Camshaft sensor Incorrect signal
98 Oxygen sensor heater Voltage low, open circuit