Kerbsidemotors guide to how to read Pre 1994 Nissan fault codes

If you have a Nissan made between 1987 and 1994 this guide can help you. It shows you how to obtain fault code information and clear codes that will cause the management light to show and affect performance.

This method will work on pretty much all Nissans made between 1986 and 1993 including Sunny/Pulsar (N13 models) Sunny ZX coupe (Can't remember the code!)Nissan Bluebird models (T12 and T72) the 200SX (S13 range) and 300ZX (Z31) UK cars. I have personally used this method on 200SX and 300ZX to great effect. If you want the procedure for Nissans after 1994 or pretty much any other Japanese car have a look at our other guides!

Anyway, how do you do it? Its pretty easy really.

Find the ECU! If it is a 200SX or 300ZX it is under the centre console. Take the thing right out so you can see the ECU
Start the car and let it idle. If it doesn't start turn it over on the starter for 10 seconds or so.
Turn the diagnostic switch fully clockwise (Small plain screwdriver) See the picture below
The LED should flash 3 times. When it has turn it fully anti-clockwise
Check the LEDs flash to confirm
The ECU will now flash the code. A red flash indicates 10 and a green flash indicates a single unit. For example, if the code was 23 the red LED would flash twice and the green LED would flash three times. Told you it was easy! The code will then repeat its self. Anyway, note the code down then switch the ignition off.

Trouble code Cause

11      Engine speed (RPM) sensor or Crankshaft sensor (CKP) intermittant signal
12      Mass air flow sensor (MAF) circuit malfunction
13      Engine temperature sensor circuit malfunction
14      Vehicle speed sensor
21      Ignition signal
22      Fuel pump open circuit
23      Closed throttle position switch
24      Park/neutral position switch (Automatics)
28      Engine coolant blower motor circuit malfunction (Cooling fan)
31    Additional Idle air control valve (IAC)
32      Starter signal
34      Knock sensor circuit malfunction
41      Intake air temperature sensor or fuel temperature sensor (Earlier models) circuit malfunction
43      Throttle position sensor
44      No faults stored
55      No faults stored
Just because a particular code is stored does not automatically mean that sensor/switch or assembly has had it. ALWAYS check the wiring to the component, the condition of the terminals and the fuses before legging it off to Nissan with your wallet flapping!

How to clear the codes

Assuming you have fixed the problem you may now have to clear the codes so the light goes out and any performance restrictions are lifted.

Turn the ignition back on
Turn the diagnostic switch clockwise fully
Let the LED flash 3 times then turn the switch fully anti clockwise
Check the LEDS flash to confirm then turn the switch fully clockwise again
Wait for teach LED to flash 4 or 5 times to indicate 'No fault found' (Code 44 or 55)
Turn the switch fully anti-clockwise and switch the ignition off again
Thats you! Put your centre console back in and feel smug every time you drive past the local Nissan dealer thinking 'I don't need you or your £50 an hour labour charges!'

Hope this all makes sense! If you enjoyed or found this guide helpful why not have a look at our other guides? If you thought it was rubbish, email us an tell us why!