BMW OBD1 DIY Diagnostic without OBD Scanner
General information
- Trouble codes are displayed by using an LED connected to one of the ECM terminals.
- The ECM fault memory can also be checked using diagnostic equipment connected to the data link connector (DLC).
Accessing – flash type
NOTE: Flash type cannot be accessed from some engine control modules (ECM).
- Ensure ignition switched OFF.
- Connect breakout box between ECM and harness multi-plug.
- ECM located in the plenum chamber.
- Motronic M1.7/3.1: Connect LED tester between breakout box terminal 8 and battery (12 volt) positive Fig. 1 .
- Motronic M1.2: Connect LED tester between breakout box terminal 15 and battery (12 volt) positive Fig. 2 .
- Switch ignition ON.
- Depress accelerator pedal fully 5 times within 5 seconds.
- V12: To access trouble codes from ECM LH bank, depress accelerator pedal fully 6 times within 5 seconds.
NOTE: V12 engine is controlled by two ECMs, RH bank and LH bank.
- Count LED flashes. Note trouble codes. Compare with trouble code table.
- Long flash indicates start of trouble code display Fig. 3 [A].
- Each trouble code consists of four groups of flashes Fig. 3 [B].
- For example: Trouble code 1211 displayed: Engine control module (ECM) Fig. 3 [B].
- LED flashes code 0000 Fig. 4 , 1000 Fig. 5 or 2000 Fig. 6 at end of trouble code output.
- Switch ignition OFF.
- Disconnect LED.
Erasing – flash type
- Depress accelerator pedal fully for 10 seconds minimum when trouble code 0000, 1000 or 2000 (end of output) is flashed.
- Switch ignition OFF.
Trouble code identification
| Flash type | Fault location | Probable cause |
| 0 | End of trouble code output | – |
| 1000 | End of trouble code output | – |
| 1211 1215 | Engine control module (ECM) – defective Mass air flow (MAF) sensor/volume air flow (VAF) sensor – incorrect signal | Disconnect ECM multi-plug for at least 10 min. – check if trouble code reappears before replacing ECM Wiring, connector(s), MAF sensor/VAF sensor |
| 1216 | Throttle position (TP) sensor – defective | Wiring, connector(s), TP sensor |
| 1218 | Engine control module (ECM) – output stage | Wiring, ECM controlled components |
| 1221 | Heated oxygen sensor (HO2S) – circuit malfunction | Wiring, connector(s), HO2S |
| 1222 1223 | Heated oxygen sensor (HO2S) – range/performance problem Engine coolant temperature (ECT) sensor – malfunction | Wiring, intake/exhaust leak, fuel level low, fuel pressure, EVAP canister purge valve, injector(s), HO2S, ECM Wiring, connector(s), ECT sensor |
| 1224 | Intake air temperature (IAT) sensor – malfunction | Wiring, connector(s), IAT sensor |
| 1225 | Knock sensor (KS) 1 – defective | Wiring, connector, KS incorrectly tightened |
| 1226 | Knock sensor (KS) 2 – defective | Wiring, connector, KS incorrectly tightened |
| 1231 | Battery voltage – too low/high | Wiring, alternator, battery |
| 1232 | Closed throttle position (CTP) switch – malfunction | Wiring, connector, CTP switch, ECM |
| 1233 | Throttle position (TP) sensor – malfunction | Wiring, TP sensor, ECM |
| 1234 | Vehicle speed sensor (VSS) – incorrect/no signal | Wiring, instrument panel, VSS |
| 1235 | Torque converter clutch (TCC) solenoid – defective | Wiring, TCC solenoid |
| 1236 1236 4 , 6 1237 1238 1238 4 1241 1241 6 | Throttle control, traction control system (TCS) – defective Engine control module (ECM)/ABS control module communication, ASR system AC compressor clutch relay – malfunction Intake manifold air control solenoid – circuit malfunction Engine control module (ECM) – unused output stage Engine control module (ECM) – no supply voltage Engine control module (ECM)/ABS control module communication, traction control system (TCS) | Wiring, connector(s), throttle control system Wiring, ABS trouble code(s) stored, ECM Wiring, AC compressor clutch relay Wiring, connector, intake manifold air control solenoid Wiring short to earth/positive, ignore flash code if terminal 18 not connected Wiring, fuse(s), battery Wiring, ABS trouble code(s) stored, ECM |
| 1241 4 | Engine control module (ECM), electronic throttle system (ETS) – overrun torque control | Wiring short to positive, ECM |
| 1242 | AC control module/engine control module (ECM) communication – malfunction | Wiring, AC control module |
| 1243 | Crankshaft position (CKP) sensor/engine speed (RPM) sensor – incorrect/no signal | Wiring, CKP sensor/RPM sensor |
| 1244 | Camshaft position (CMP) sensor – range/performance problem | Wiring, CMP sensor |
| 1245 | Engine control module (ECM)/transmission control module (TCM) communication – short to earth | Wiring, ECM, TCM |
| 1247 | Ignition circuit – primary circuit | Wiring, ignition coil(s) |
| 1251 | Injector(s), group 1 – circuit malfunction | Wiring, injector(s) |
| 1251 4 | Injector, cyl. 1 – circuit malfunction | Wiring, injector |
| 1252 | Injector(s), group 2 – circuit malfunction | Wiring, injector(s) |
| 1252 4 | Injector, cyl. 5 – circuit malfunction | Wiring, injector |
| 1253 | Injector, cyl. 3 – circuit malfunction | Wiring, injector |
| 1254 | Injector, cyl. 6 – circuit malfunction | Wiring, injector |
| 1255 | Injector, cyl. 2 – circuit malfunction | Wiring, injector |
| 1256 | Injector, cyl. 4 – circuit malfunction | Wiring, injector |
| 1261 | Fuel pump relay – malfunction | Wiring, connector(s), fuel pump relay |
| 1262 | Idle speed control (ISC) actuator/idle air control (IAC) valve – malfunction | Wiring, connector(s), ISC actuator/IAC valve |
| 1263 | Evaporative emission (EVAP) canister purge valve – malfunction | Wiring, connector(s), EVAP canister purge valve |
| 1264 | Oxygen sensor heater relay – malfunction | Wiring, connector, oxygen sensor heater relay |
| 1265 | Malfunction indicator lamp (MIL) – short to earth/positive | Wiring short to earth/positive, MIL |
| 1268 | Mixture adjustment resistor – signal too low/high | Wiring, mass air flow (MAF) sensor |
| 1271 | Ignition circuit – defective | Wiring, connector, ignition coil, ECM |
| 1271 4 | Ignition circuit, cyl. 1 – defective | Wiring, connector, ignition coil, ECM |
| 1272 | Ignition circuit, cyl. 5 – defective | Wiring, connector, ignition coil, ECM |
| 1273 | Ignition circuit, cyl. 3 – defective | Wiring, connector, ignition coil, ECM |
| 1274 | Ignition circuit, cyl. 6 – defective | Wiring, connector, ignition coil, ECM |
| 1275 | Ignition circuit, cyl. 2 – defective | Wiring, connector, ignition coil, ECM |
| 1276 | Ignition circuit, cyl. 4 – defective | Wiring, connector, ignition coil, ECM |
| 1278 | Transmission control module (TCM) – signal | Wiring, TCM |
| 1281 | Battery voltage – too low | Wiring, alternator, battery |
| 1282 | Engine control module (ECM) – internal fault | Disconnect ECM multi-plug for at least 10 min. – check if trouble code reappears before replacing ECM |
| 1283 | Injector(s) – circuit malfunction | Wiring, injector(s) |
| 1285 | Engine control module (ECM)/alarm system control module communication – alarm system active | Wiring short to positive, alarm system control module |
| 1286 | Knock control circuit – defective | Wiring, connector, KS incorrectly tightened, knock sensor (KS), ECM |
| 1287 | Engine control module (ECM) – electronic throttle system (ETS) signal | Wiring short to positive, ignore flash code if terminal 62 not connected |
| 1288 | Engine control module (ECM) – internal fault | ECM |
| 1288 4 | Engine control module (ECM) – automatic stability control (ASR)/overrun torque control defective | Wiring, ETS, ABS trouble code(s) stored |
| 1444 | No fault found | – |
| 1513 | Engine control module (ECM) – unused output stage | Wiring short to earth/positive, ignore flash code if terminal 18 not connected |
| 2000 | End of trouble code output | – |
| 2211 | Engine control module (ECM) – defective | Disconnect ECM multi-plug for at least 10 min. – check if trouble code reappears before replacing ECM |
| 2215 | Mass air flow (MAF) sensor/volume air flow (VAF) sensor – incorrect signal | Wiring, connector(s), MAF sensor/VAF sensor |
| 2218 | Engine control module (ECM) – output stage | Wiring, ECM controlled components |
| 2221 | Heated oxygen sensor (HO2S) – circuit malfunction | Wiring, connector(s), HO2S |
| 2222 | Heated oxygen sensor (HO2S) – range/performance problem | Wiring, intake/exhaust leak, fuel level low, fuel pressure, evaporative emission (EVAP) canister purge valve, injector(s), HO2S, ECM |
| 2223 | Engine coolant temperature (ECT) sensor – malfunction | Wiring, connector(s), ECT sensor |
| 2224 | Intake air temperature (IAT) sensor – malfunction | Wiring, connector(s), IAT sensor |
| 2231 | Battery voltage – too low/high | Wiring, alternator, battery |
| 2232 | Closed throttle position (CTP) switch – malfunction | Wiring, connector, CTP switch, ECM |
| 2233 | Throttle position (TP) sensor – malfunction | Wiring, TP sensor, ECM |
| 2234 | Vehicle speed sensor (VSS) – incorrect/no signal | Wiring, instrument panel, VSS |
| 2235 | Torque converter clutch (TCC) solenoid – defective | Wiring, TCC solenoid |
| 2236 | Engine control module (ECM)/ABS control module communication, automatic stability control (ASR) system | Wiring, ABS trouble code(s) stored, ECM |
| 2237 | AC compressor clutch relay – malfunction | Wiring, AC compressor clutch relay |
| 2241 | Engine control module (ECM)/ABS control module communication, traction control system (TCS) | Wiring, ABS trouble code(s) stored, ECM |
| 2244 | Camshaft position (CMP) sensor – range/performance problem | Wiring, CMP sensor |
| 2245 | Engine control module (ECM)/transmission control module (TCM) communication – short to earth | Wiring, ECM, TCM |
| 2444 | No fault found | – |
| 2251 | Injector(s), group 1 – circuit malfunction | Wiring, injector(s) |
| 2252 | Injector(s), group 2 – circuit malfunction | Wiring, injector(s) |
| 2261 | Fuel pump relay – malfunction | Wiring, connector(s), fuel pump relay |
| 2263 | Evaporative emission (EVAP) canister purge valve – malfunction | Wiring, connector(s), EVAP canister purge valve |
| 2264 | Oxygen sensor heater relay – malfunction | Wiring, connector, oxygen sensor heater relay |
| 2265 | Malfunction indicator lamp (MIL) – short to earth/positive | Wiring short to earth/positive, MIL |
| 2268 | Mixture adjustment resistor – signal too low/high | Wiring, mass air flow (MAF) sensor |
| 2278 | Transmission control module (TCM) – signal | Wiring, TCM |
| 2513 | Engine control module (ECM) – unused output stage | Wiring short to earth/positive – ignore flash code if terminal 18 not connected |
| 4444 | No fault found | – |
| Scanner type | Fault location | Probable cause |
| – | No fault found | – |
| 0 | Engine control module (ECM) – undefined fault | – |
| 1 | Engine control module (ECM) – defective | ECM |
| 1 1 | Fuel pump relay – malfunction | Wiring, connector(s), fuel pump relay |
| 2 | Idle speed control (ISC) actuator/idle air control (IAC) valve – malfunction | Wiring, connector(s), ISC actuator/IAC valve |
| 3 2 | Fuel pump relay – malfunction | Wiring, connector(s), fuel pump relay |
| 3 | Injector(s), cyl. 1 & 3 or cyl. 2, 4, 6 & 8, 10, 12 – circuit malfunction | Wiring, injector(s) |
| 3 3 | Injector(s), cyl. 2 & 4 – circuit malfunction | Wiring, injector(s) |
| 3 4 | Injector(s), cyl. 1 – circuit malfunction | Wiring, injector |
| 4 | Injector(s), cyl. 3 – circuit malfunction | Wiring, injector |
| 5 | Evaporative emission (EVAP) canister purge valve – malfunction | Wiring, connector(s), EVAP canister purge valve |
| 5 4 | Injector(s), cyl. 2 – circuit malfunction | Wiring, injector |
| 6 | Injector(s) – circuit malfunction | Wiring, injector(s) |
| 7 | Mass air flow (MAF) sensor/volume air flow (VAF) sensor – incorrect signal | Wiring, connector(s), MAF sensor/VAF sensor |
| 10 | Heated oxygen sensor (HO2S) – range/performance problem | Wiring, intake/exhaust leak, fuel level low, fuel pressure, evaporative emission (EVAP) canister purge valve, injector(s), ECM |
| 12 | Throttle position (TP) sensor – defective | Wiring, connector(s), TP sensor |
| 15 | Knock sensor (KS) 1 – defective | Wiring, connector, KS incorrectly tightened, KS |
| 16 | Injector(s), cyl. 1, 3, 5 & 7, 9, 11 – circuit malfunction | Wiring, injector(s) |
| 16 1 | Camshaft position (CMP) sensor – range/performance problem | Wiring, CMP sensor |
| 17 | Injector(s), cyl. 2, 4, 6 & 8, 10, 12 – circuit malfunction | Wiring, injector(s) |
| 18 | Engine control module (ECM) – unused output stage | Wiring short to earth/positive, ignore flash code if terminal 18 not connected |
| 18 5 | Intake manifold air control solenoid – circuit malfunction | Wiring, connector, intake manifold air control solenoid |
| 19 | Engine control module (ECM) – unused output stage | Wiring short to earth/positive, ignore flash code if terminal 18 not connected |
| 23 | Oxygen sensor heater relay – malfunction | Wiring, connector, oxygen sensor heater relay |
| 23 4 | Ignition circuit, cyl. 2 – defective | Wiring, connector, ignition coil, ECM |
| 24 | Engine control module (ECM)/transmission control module (TCM) communication | Wiring short to earth, TCM trouble code(s) stored |
| 24 4 | Ignition circuit, cyl. 3 – defective | Wiring, connector, ignition coil, ECM |
| 25 | Ignition circuit, cyl. 1 – defective | Wiring, connector, ignition coil, ECM |
| 26 | Battery voltage – too low | Wiring, alternator, battery |
| 28 | Heated oxygen sensor (HO2S) – circuit malfunction | Wiring, connector(s), HO2S |
| 29 | Idle speed control (ISC) actuator/idle air control (IAC) valve – malfunction | Wiring, connector(s), ISC actuator/IAC valve |
| 31 | Injector, cyl. 5 – circuit malfunction | Wiring, injector |
| 32 | Injector(s), cyl. 2 & 4 – circuit malfunction | Wiring, injector(s) |
| 32 6 | Injector(s), cyl. 1, 3, 5 & 7, 9, 11 – circuit malfunction | Wiring, injector(s) |
| 32 3 | Injector(s), cyl. 1 & 3 – circuit malfunction | Wiring, injector(s) |
| 32 4 | Injector, cyl. 6 – circuit malfunction | Wiring, injector |
| 33 | Injector, cyl. 4 – circuit malfunction | Wiring, injector |
| 36 | Evaporative emission (EVAP) canister purge valve – malfunction | Wiring, connector(s), EVAP canister purge valve |
| 37 | Battery voltage – too low/high | Wiring, alternator, battery |
| 37 1 | Oxygen sensor heater relay – malfunction | Wiring, connector, oxygen sensor heater relay |
| 38 | Engine control module (ECM)/ABS control module communication, acceleration skid control (ASR) system | Wiring, ABS trouble code(s) stored, ECM |
| 41 | Mass air flow (MAF) sensor/volume air flow (VAF) sensor – incorrect signal | Wiring, connector(s), MAF sensor/VAF sensor |
| 42 | Knock sensor (KS) 2 – defective | Wiring, connector, KS incorrectly tightened, KS |
| 44 | Intake air temperature (IAT) sensor – malfunction | Wiring, connector(s), IAT sensor |
| 45 | Engine coolant temperature (ECT) sensor – malfunction | Wiring, connector(s), ECT sensor |
| 46 | AC condenser blower motor relay – short to positive | Wiring short to positive, AC condenser blower motor relay, ECM |
| 46 4 | Engine control module (ECM) – output stage | Wiring, ECM controlled components |
| 48 | AC compressor clutch relay – malfunction | Wiring, AC compressor clutch relay |
| 50 | Ignition circuit, cyl. 4 – defective | Wiring, connector, ignition coil, ECM |
| 51 | Transmission control module (TCM) – signal | Wiring, TCM |
| 51 4 | Ignition circuit, cyl. 6 – defective | Wiring, connector, ignition coil, ECM |
| 52 | Closed throttle position (CTP) switch – malfunction | Wiring, connector, CTP switch, ECM |
| 52 4 | Ignition circuit, cyl. 5 – defective | Wiring, connector, ignition coil, ECM |
| 53 | Throttle position (TP) sensor/wide open throttle (WOT) switch – malfunction | Wiring, TP sensor, ECM |
| 54 | Engine control module (ECM)/transmission control module (TCM) communication | Wiring short to earth, TCM trouble code(s) stored |
| 54 1 | Battery voltage – too low/high | Wiring, alternator, battery |
| 55 | Ignition circuit – defective | Wiring, connector, ignition coil, ECM |
| 62 | Engine control module (ECM) – electronic throttle system (ETS) signal | Wiring short to positive, ignore flash code if terminal 62 not connected |
| 63 | Torque converter clutch (TCC) solenoid – defective | Wiring, TCC solenoid |
| 64 | Engine control module (ECM)/transmission control module (TCM) communication – short to earth | Wiring, TCM trouble code(s) stored, ECM, TCM |
| 67 | Crankshaft position (CKP) sensor/engine speed (RPM) sensor – incorrect/no signal | Wiring, CKP sensor/RPM sensor |
| 70 | Heated oxygen sensor (HO2S) – circuit malfunction | Wiring, connector(s), HO2S |
| 73 | Vehicle speed sensor (VSS) – incorrect/no signal | Wiring, instrument panel, VSS |
| 76 | Mixture adjustment resistor – signal too low/high | Wiring, mass air flow (MAF) sensor |
| 77 | Intake air temperature (IAT) sensor – malfunction | Wiring, connector(s), IAT sensor |
| 78 | Engine coolant temperature (ECT) sensor – malfunction | Wiring, connector(s), ECT sensor |
| 81 | Engine control module (ECM)/immobilizer control module communication – malfunction | Wiring, electrical interference, immobilizer control module, ECM |
| 81 4 | Engine control module (ECM)/alarm system control module communication – alarm system active | Wiring short to positive, alarm system control module |
| 82 | Engine control module (ECM)/ABS control module communication, traction control system (TCS) | Wiring, ABS trouble code(s) stored, ECM |
| 82 4 | Engine control module (ECM), electronic throttle system (ETS) – overrun torque control | Wiring short to positive, ECM |
| 83 | Throttle control, traction control system (TCS) – defective | Wiring, connector(s), throttle control system |
| 83 4 | Engine control module (ECM) – acceleration skid control (ASR) defective | Wiring short to positive, ECM |
| 85 | Air conditioning (AC) control module/engine control module (ECM) communication – malfunction | Wiring, AC control module |
| 100 | Engine control module (ECM) – output stage | Wiring, ECM controlled components |
| 200 | Engine control module (ECM) – defective | Disconnect ECM multi-plug for at least 10 min. – check if trouble code reappears before replacing ECM |
| 201 | Heated oxygen sensor (HO2S) – range/performance problem | Wiring, intake/exhaust leak, fuel level low, fuel pressure, evaporative emission (EVAP) canister purge valve, injector(s), HO2S, ECM |
| 202 | Engine control module (ECM) – internal fault | Disconnect ECM multi-plug for at least 10 min. – check if trouble code reappears before replacing ECM |
| 203 | Ignition circuit – primary circuit | Wiring, ignition coil(s) |
| 204 | Engine control module (ECM) – acceleration skid control (ASR)/overrun torque control defective | Wiring, trouble code(s) stored in other system(s) |
| 206 | Knock control circuit – defective | Wiring, connector, knock sensor (KS), ECM |
| 207 | Knock control circuit – range/performance problem | Wiring, connector, KS incorrectly tightened, knock sensor (KS) |
| 220 | Engine control module (ECM) – immobilizer active | Incorrect/damaged key, incorrectly coded, ECM/immobilizer replacement without coding, wiring, immobilizer defective |
| 300 | Engine control module (ECM) – engine cannot be started | Wiring, engine speed (RPM) sensor, mass air flow (MAF) sensor/volume air flow (VAF) sensor, fuel pump relay, ignition system, injector(s), fuel pressure, throttle control system |