Opel/Vauxhall Fault Codes

Bosch Motronic fault code listing
This covers Motronic version 2.5 and 2.8 ECUs, fitted in Vauxhall/Opel vehicles from approximately 1990 onwards, which control fuel and ignition systems. Fault codes are shown with the corresponding fault. Fault codes in related, electronically-controlled vehicle systems such as ABS, Traction Control, and 4x4. This mainly pertains to the Vauxhall Cavalier, Carlton (Vectra-A and Omega-A in Europe, respectively), Senator, and Calibra.
Engine ECU
12 Diagnosis initiation/separator (indicates beginning/end of fault code list)
13 Oxygen sensor - open circuit
14 Coolant temperature sensor - voltage low
15 Coolant temperature sensor - voltage high
16 Knock signal circuit - no voltage change
17 Knock signal circuit 2 - no voltage change (V6 models only)
18 Knock control module (ECU)
19 Incorrect RPM signal (Crankshaft sensor - incorrect signal)
21 Throttle position sensor - voltage high
22 Throttle position sensor - voltage low
23 Knock sensor - out of range
24 Speed sensor (MPH)
25 Injector 1 - voltage high
26 Injector 2 - voltage high
27 Injector 3 - voltage high
28 Injector 4 - voltage high
29 Injector 5 - voltage high/ Fuel pump relay voltage low (non-V6 models)
30 Injector 6 - voltage high (V6 models only)
31 No engine RPM signal (engine not running, or no Crankshaft sensor signal)
32 Fuel pump relay - voltage high
33 MAP sensor - voltage high
34 MAP sensor - voltage low
35 Idle air control valve stepper motor (no idle speed control)
38 Oxygen sensor - voltage low (weak mixture)
39 Oxygen sensor - voltage high (rich mixture)
41 1 gear indent switch - voltage low
42 1 gear indent switch - voltage high
43 EGR system
44 Oxygen circuit - voltage low (weak mixture)
45 Oxygen circuit - voltage high (rich mixture)
47 Linear EGR position
48 Battery - voltage low
49 Battery - voltage high
51 ECU memory failure
52 Check engine light - voltage high
53 Fuel pump relay - voltage low
54 Fuel pump relay - voltage high
55 ECU faulty
56 Idle air control valve - voltage low/high
57 Idle air control valve - voltage high/low
61 Fuel tank vent valve - voltage low
62 Fuel tank vent valve - voltage high
63 EST line coil cylinders 2 & 3 - voltage low
64 EST line coil cylinders 1 & 4 - voltage low
65 Idle CO potentiometer - voltage low
66 Idle CO potentiometer - voltage high
67 Idle position switch - voltage low (idle position switch not opening)
69 Intake air temperature sensor - voltage low
71 Intake air temperature sensor - voltage high
72 Full position switch - voltage high
73 Air flow sensor - voltage low
74 Air flow sensor -voltage high
75 Torque control - voltage low
76 Torque control - continuous
79 Full load inhibitor - voltage low (traction control signal)
81 Injector valve 1 - voltage low
82 Injector valve 2 - voltage low
83 Injector valve 3 - voltage low
84 Injector valve 4 - voltage low
85 Injector valve 5 - voltage low (V6 models only)
86 Injector valve 6 - voltage low (V6 models only)
87 A/C cut-off relay - voltage low
88 A/C cut-off relay - voltage high
92 Camshaft sensor failure
93 Hall sensor - voltage low
94 Hall sensor - voltage high
95 Hot start valve - voltage low
96 Hot start valve - voltage high
97 Ignition/Injection cut off - voltage high (traction control signal)
113 Boost control out of range (turbo models only)
114 Boost pressure (idle) above upper limit (turbo models only)
115 Boost pressure (full) below upper limit (turbo models only)
116 Boost pressure (full above upper limit (turbo models only)
117 Wastegate valve - voltage low (turbo models only)
118 Wastegate valve - voltage high (turbo models only)
Anti-Lock Braking System ECU
16 Left-front solenoid
17 Right-front solenoid
18 Rear solenoids
19 Solenoids relay circuits
25 Faulty sensor toothed ring
35 Pump relay circuits (hydraulic modulator)
37 Stop lamp switch (brake pedal switch)
39/44 Left front RPM sensor (air gap between sensor and toothed ring, & sensor operation)
41/45 Left front RPM sensor (resistance & connections)
42/46 Right front RPM sensor (air gap between sensor and toothed ring, & sensor operation)
43/47 Right front RPM sensor (resistance & connections)
48 System voltage wrong (alternator or battery)
55 Faulty ECU
Four-wheel drive ECU
15 Oil temperature sensor - voltage high
24 No speed signal
31 No engine RPM signal
32 Pressure switch faulty
33 Solenoid valve - voltage high/transfer box overheated to 160°C on 1992 models
34 Solenoid valve - voltage low
37 Brake lamp switch
39 No ABS signal, or 0MPH and 2300RPM for more than 15 seconds
55 ECU faulty
71 Brake switch - voltage high
72 Brake switch - voltage low
73 Car stopped without braking from over 37mph
74 Power Assisted Steering PAS pressure less than 10 bar
75 Oil temperature sensor - voltage low/transfer box overheated to 160°C or 140°C for over 118MPH.
(Note that codes 15,39,71-75 apply only to models from roughly 1994 onwards, with electronic speedometers)
Traction Control ECU (V6 models and Astra GSi only)
14 Coolant temperature sensor - voltage low
15 Coolant temperature sensor - voltage high
21 Throttle position sensor - voltage high
22 Throttle position sensor - voltage low
26 Traction control throttle position sensor - voltage high (throttle motor resistor failure; V6 models only)
27 Traction control throttle position sensor - voltage low (throttle motor resistor failure; V6 models only)
31 No engine RPM signal
37 Stop lamp switch (brake pedal switch)
39 Left front RPM sensor (ABS fault)
42 Right front RPM sensor (ABS fault)
44 Left rear RPM sensor (ABS fault)
46 Right rear RPM sensor (ABS fault)
55 ECU fault
57 ABS status - signal low (indicates ABS system fault, not TC system fault)
58 ABS status - open circuit
63 Throttle motor - open circuit
64 Throttle motor - short circuit
82 On/off switch voltage low (dashboard switch)
Alarm ECU (Factory fitted alarms only)
18 Fault with disarm signal
25 Horn - Voltage Low (Horn O/C or fuse blown)
26 Indicator left - open circuit
27 Indicator right - open circuit
28 Ultrasonic sensor driver side - open circuit or incorrect voltage
29 Ultrasonic sensor passenger side - open circuit or incorrect voltage
32 Boot (trunk) sensor caused an alarm condition
33 Bonnet (hood) sensor caused an alarm condition
34 Doors caused an alarm condition
35 Ignition turned on caused an alarm condition
36 Immobilization circuit - open circuit (starter circuit triggered causing alarm)
37 Radio caused an alarm condition
38 Ultrasonics caused an alarm condition
39 Fault with disarm signal. (central locking fuse blown, causing alarm condition)
40 Two alarm triggers at the same time.
41 Spare alarm input caused alarm condition
46 Rear Window smashed caused an alarm condition  ('92 onwards models only)
52 Horn Voltage Low - Horn O/C or fuse blown
55 ECU fault
Automatic Gearbox ECU
17 Solenoid 1-2/3-4 - voltage low
21 Throttle position sensor - voltage high
22 Throttle position sensor - voltage low
23 Coolant temperature switch - voltage high
25 Solenoid 1-2/3-4 - voltage high
26 Solenoid 2-3 - voltage low
27 Connection solenoid 2-3/solenoid TCC
28 Solenoid 2-3 - voltage high
29 TCC Solenoid - voltage low
31 No engine RPM signal
32 Pressure regulator solenoid - voltage low
33 Pressure regulator solenoid - current high
36 TCC Solenoid - voltage high
38 No transmission input RPM signal
39 No transmission output RPM signal
41 Gear error - hydraulic fault
42 Pressure regulator solenoid - short circuit
47 Down shift protection fault
48 Battery - voltage low
49 Battery - voltage high
56 Selector switch - incorrect signal
65 AT oil temperature sensor - voltage high
66 AT oil temperature sensor - voltage low/high
67 AT oil temperature sensor - voltage high
75 Transmission switch - voltage low
76 Engine TPS load signal incorrect
77 Kickdown switch - voltage low
78 AT shift time - too long
Simtec 56 Fault code listing
Models from about 1995-1996 on will probably use codes from this list.
13 Oxygen Sensor - open circuit
14 Coolant temperature sensor - voltage low
15 Coolant temperature sensor - voltage high
16 Knock sensor signal circuit
19 Incorrect RPM signal
21 Throttle position sensor - voltage high
22 Throttle position sensor - voltage low
23 Knock signal - out of range
24 No vehicle speed signal
25/26/27/28/29/30 Injector valve 1/2/3/4/5/6 - voltage high (injector(s) short-circuited to battery, or injection signal not present)
37 Check light - voltage low
38 Oxygen sensor circuit - voltage high
39 Oxygen sensor circuit - voltage low
44 Oxygen sensor - lean exhaust
45 Oxygen sensor - rich exhaust
48 Battery - voltage low
49 Battery - voltage high
52 Fuel pump relay - voltage low
53 Fuel pump relay - voltage high
54 Fuel pump relay 0 - voltage high
55 ECU memory fault
56 Idle air control valve - voltage high
57 Idle air control valve - voltage low
61 Fuel tank vent valve - voltage low
62 Fuel tank vent valve - voltage high
69 Intake air temperature
71 as above
73 Mass air flow temperature
74 Mass air flow temperature
75 Torque control - voltage low
76 Torque control - continuous
81/82/83/84/85/86 - Injector valve 1/2/3/4/5/6 - voltage low (injector(s) short  circuit to ground)
87 A/C cut-off relay - voltage low
88 A/C cut-off relay - voltage high
91 Oxygen heating - voltage high
92 Camshaft position sensor - incorrect signal
93 Camshaft position sensor - voltage low
94 Camshaft position sensor - voltage high
95 Hot start valve - voltage low
96 Hot start valve - voltage low
97 Traction control module - incorrect signal
98 Oxygen Sensor heating - voltage low
113 Turbo wastegate control - boost pressure high
114 Turbo boost pressure (idle) - above upper limit
115 Turbo boost pressure (full) - below upper limit
116 Turbo boost pressure - above upper limit
117 Turbo wastegate regulating valve - voltage low
118 Turbo wastegate regulating valve - voltage high
119 Manifold absolute pressure (MAP) sensor - range or performance
121 Oxygen sensor - lean mixture
122 Oxygen sensor - rich mixture
123 Intake manifold air control solenoid (1) - blocked
124 Intake manifold air control solenoid (2) - blocked
125 MAP sensor - below upper limit
126 MAP sensor - above upper limit
129 Exhaust gas recirculation (EGR) system - voltage low
131 EGR system - voltage high
132 EGR system - incorrect signal
133 EGR system (2) - voltage high/low (unclear)
134 EGR system (2) - voltage low/high (unclear)
135 Malfunction indicator lamp - voltage low
136 ECU memory fault
137 ECU - temperature high
138 MAP sensor - voltage low
139 MAP sensor - voltage high
143 Immobiliser - no signal/wrong signal
144 Immobiliser - no signal
145 Immobiliser - wrong signal