2001 Saturn Immobilizer problem

Sounds like you have a problem with the coolant temp sensor or it related wiring.

If your car has the yellow car key symbol on the instrument cluster when you turn the key to on shown activated below it has an If your car has the yellow car/key symbol on the instrument cluster when you turn the key to ON shown activated below it has an immobilizer This light comes on for a second but quickly goes out when turning the car on and all is normal If it stays on you have an issue immobilizer This light comes on for a second but quickly goes out when turning the car on and all is normal If it stays on you have an issue

Make sure the key isn't on a keyring, and if you have a spare key try holding it against the ignition barrel whilst trying to start the car. Failing that, it's an auto electrician job. China OBD2 car diagnostic tools wholesale on CareUCar

You have an electronic immobilizer key recognition problem. Your key chip is not recognized by the transponder antenna fitted on the ignition switch barrel. Do you have this warning symbol lightning on the dashboard?



This warning lamp indicates that the engine is locked by the immobilizer system, and the engine start sequence must be repeat again.

From year 1995 in Audi-VW (VAG) cars is used engine immobilizer. The VAG group immobilizer system consists of an immobilizer ECU which controls the recognition of keys and the Engine Management ECU system. Immobilizer is activated when the ignition key is removed and, together with the engine control unit, largely prevents unauthorized starting of the engine. The system uses a transmitter and receiver unit in the ignition key (transponder). Whenever an attempt is made to start the engine, it transmits a new code to the car's electronics. The immobilizing is only cancelled and car motor electronic receives permission to start engine if the key sends a right authorization code.


Use another ignition key that you have, and start the engine.


You will need to programm all ignition keys using suitable diagnostic equipment (VAS, VAG-Com) connected to the data link connector of the car.

you are looking at two unrelated things. when the car died, the oil pressure dropped off causing the light to come on. this is normal. when the key is on but the engine is not running, there is no oil pressure so the light will be on. dont be concerned about the oil light and start diagnosing your no start.

Sounds like the immobilizer. Does the key light in the dash stay on when you turn it over?

Immobilizer is the code that the key has (it's actually a radio frequency identification or RFID chip). If the key code doesn't match the car code, the car will turn over but won't stay running.

If this is the problem, you'll need to take the car to a dealer to get the key recoded.

Many cars these days are equipped with an immobilizer. (you can find more information about the immobilizer in your owner's manual). The immobilizer allows the engine to run only if the correct key is used. If your car has an immobilizer, you probable see a "Security" or Key-shaped light coming on on the dashboard every time you turn the ignition ON. If this light is flashing when you turn the ignition ON, it could mean that there is some problem with an immobilizer or the system does not recognize the key. If the immobilizer doesn't recognize the key, the engine wold not start at all, or would start and then die in few seconds.
You can try a spare key, if it won't work, your dealer is the place to call. Sometimes, the key is just need to be reprogrammed. On some cars you can find the information how to reprogram the key in the owner's manual.

immobilizer has kicked in

Check the wires on the alternator