What are the meaning of the displays on dash board

Sounds like the dash display has a shorted circuit board, pull the dash display out and have it repaired.

Never try to reset the Immobilizer. It is advised to consult a programming personnel.

it means there is a code in the computer that needs to be checked and repaired in order to turn off the light.

The warning lights should be listed in your owners manual. It could be a warning for one of the gauges, or engine/transmission problems.
They are more common on Toyota Prius.

have you checked at all if there are any fuses,relays or bad contacts are the cause?

You must put it up in the air and have someone run the engine while you attempt to locate the leak.

There is a lever to open the trunk next to the fuel door lever under the left front side of the driver seat.

If the lever is broken or missing, check if the back seats recline, allowing access to the trunk. Crawl in and pull the lever going to the lock cylinder.

If neither suggestion works, call a locksmith.

if by heater core you mean matrix then yes the only civil way to remove it and replace it is to taker dash board out?

the fuel light might possibly just be burned out, easy fix, the abs light could be because of low brake fluid pressure, or some other brake problem, hope this helps

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