General Information
- Engine control module (ECM) incorporates self-diagnosis function
- Malfunction indicator lamp (MIL) will illuminate if certain faults are recorded
- ECM operates in backup mode if sensors fail, to enable vehicle to be driven to workshop
- Trouble codes can be displayed by the red LED (see Image # 3; callout 1) in the engine control module (ECM) and the MIL lamp in diagnostic mode 2, or using a suitable code reader
Accessing Trouble Codes
Self-Diagnosis – Mode 1- Access engine control module (ECM):
- Except 240SX – center fascia – 1
- 240SX – RH kick panel – 2
- Switch ignition ON
- Check MIL and red LED in ECM illuminate
- Start engine. Allow to idle
- If MIL and LED extinguish, no trouble codes have been recorded
- If MIL and LED remain illuminated, access trouble codes
- Switch ignition ON. Do NOT start engine.
- Turn diagnostic mode selector on ECM fully clockwise (see Image # 3; callout 2)
- Wait at least 2 seconds
- Turn diagnostic mode selector on ECM fully counterclockwise (see Image # 3; callout 2)
- Self-diagnosis now in Mode 2
- MIL and red LED in ECM should flash
- Count flashes and compare with trouble code table below.
- Long flashes indicate the ‘tens’ of the trouble code
- Short flashes indicate the ‘units’ of the trouble code
- A short pause separates each flash
- A long pause separates each trouble code
- Switch ignition OFF
- Self-diagnosis will return to Mode 1
Clearing Trouble Codes
- Switch ignition ON. Do NOT start engine
- Turn diagnostic mode selector on ECM fully clockwise
- Wait at least 2 seconds
- Turn diagnostic mode selector on ECM fully counterclockwise
- Self-diagnosis now in Mode 2
- Turn diagnostic mode selector on ECM fully clockwise
- Wait at least 2 seconds
- Turn diagnostic mode selector on ECM fully counterclockwise
- Self-diagnosis will return to Mode 1
- Trouble codes now erased
- Switch ignition OFF
Trouble Codes
| 93-94 Altima 2.4L Engine Code: KA24DE | ||
|---|---|---|
| 91-94 Sentra/NX 1.6L Engine Code: GA16DE | ||
| 91-94 Sentra/NX 2.0L Engine Code: SR20DE | ||
| 90-92 Stanza 2.4L Engine Code: KA24E | ||
| 91-94 240SX 2.4L Engine Code: KA24DE | ||
| Trouble code | Fault location | Probable cause |
| 11 | Crankshaft position (CKP) sensor circuit malfunction | Wiring, CKP sensor, ECM |
| 12 | Mass air flow (MAF) sensor -range/ performance problem | Wiring, MAF sensor, ECM |
| 13 | Engine coolant temperature (ECT) sensor range/performance problem | Wiring, ECT sensor, ECM |
| 14 | Vehicle speed sensor (VSS) -malfunction | Wiring, VSS, ECM |
| 21 | Ignition coil -no primary signal | Wiring, ignition coil!module, ignition system, ECM |
| 31 | Engine control module (ECM) -malfunction | ECM |
| 32 | Exhaust gas recirculation (EGR) system -control valve malfunction | Wiring, hose leak/blockage, EGR cut OFF solenoid, ECM |
| 33 | Heated oxygen sensor (H02S) -circuit malfunction | Wiring, H02S, intake/fuel system, injector, ECM |
| 34 | Knock sensor (KS) -circuit malfunction | Wiring, KS, ECM |
| 35 | Exhaust gas recirculation temperature (EGRT) sensor-circuit malfunction | Wiring, EGRT sensor, ECM |
| 41 | lntake air temperature (lAT) sensor circuit malfunction | Wiring, IAT sensor, ECM |
| 43 | Throttle position (TP) sensor -circuit malfunction | Wiring, TP sensor, ECM |
| 45 | Injector leak -malfunction | lnjector, fuel system, ECM |
| 54 | ECM/TCM -communication malfunction | Wiring, ECM, TCM |
| 55 | No faults detected | – |