Nissan Repair: Airbag light on constantly and fuel gauge does what it likes.

Question
QUESTION: I wonder if you can offer some advice. Since I bought the car I have had 2 main issues. These are a fuel gauge that is not functioning properly and my airbag light stays on constantly. I have tried to clean the sender unit to deal with the fuel gauge (admittedly I didn't spend a huge amount of time on this) and since then rather than it not working at all, sometimes it tends to work for a while just after the tank is filled, after that it will do whatever it pleases. As for the airbag, I have tried changing the fuse. That worked for about 3 start ups then went back to being on constantly. I have changed the airbag ecu unit and that had no effect. Then I changed the fuse again, so now new computer, new fuse and still no joy. I wonder if it might be a fault with a cable in the dash? any help you can offer is gratefully received, thank you.

ANSWER: Hi Julie -

Please tell me the make, year and model of your Nissan.

Thank you
Calvin

---------- FOLLOW-UP ----------

QUESTION: Sorry, yes it is a Nissan Primera SE + 2001. 2ltr petrol.

Answer
Hi Julie -

I just wanted to confirm if the airbag light is constantly on, or blinking.

If it is on - try disconnecting the negative battery cable for at least 10 seconds. Check the connections under the seat to ensure that it is tight.

If it is blinking, a little more detailed:       
Insert the key into the ignition and turn the key to ON.
Notice that the light will stay on and then start blinking. After turning the key to ON, wait until the light turns to off, to start the blinking process, and then switch the key OFF and remove the key.
Wait 5 seconds. Stick the key back in the ignition and repeat step 1.
Wait 5 seconds and repeat step 1. This should be completed three times. The status light may have a different blinking pattern at this point. Simply follow the same simple steps. Insert the key into the ignition and turn it to ON. Wait until the light turns off to start the blinking process and quickly turn the key to OFF and remove the key. Do this process a total of 2 more times.
When you are complete, you should have inserted the key and removed it for a total of 6 times. Now turn the key and start the car. The status light should stay lit and finally turn off as it normally should. If the light begins to blink again, repeat the steps above.

Hope this helps -
aloha
Calvin