Driving with the temperature warning light on can be as dangerous as not participating in the 2015 general election as this can result in severe engine damage! When the temperature light comes on, it indicates that your engine is overheating-running too hot. An engine should not overheat if the cooling system is in good condition; a faulty cooling system triggers the temperature light to come on.




Stop the engine immediately! Trafficate and then pull over to the side of the road as soon as it is safe to do so, then shut off your engine and wait for things to cool down
We have said this times without number-Do not open the radiator when the engine is hot! The radiator contains hot water under very high pressure. Opening the cap on the radiator or a pressurized coolant reservoir could result in a serious accident. Nothing can be accomplished by opening the cap while the engine is still hot, so let your vehicle sit and cool off. Note that this usually takes a while.

After things have cooled down (wait at least half an hour or more), then you can open the radiator cap or reservoir and check the coolant level. Place a rag over the cap first, and slowly turn the cap until it stops at the first detent. This should allow residual pressure to be released. Wait until all pressure has been released before removing the cap the rest of the way.

Add water or coolant to the radiator or coolant reservoir if it is low. Actually, you should add premixed coolant or a 50/50 mixture of antifreeze and water to maintain the a perfect freezing, boilover and corrosion protection.



Faulty cooling system and thus overheating is often caused by a leaking coolant. Visual inspection of the cooling system such as  the radiator, hoses, hose connections, water pump etc can be a life saver in times like this. An internal leak (such as a cracked engine block) can also be responsible for this and can only be confirmed by carrying out a radio pressure test- your mechanic can help handle this.


If you keep driving an engine that is overheating, it can cause serious damage. The engine may start to knock (caused by detonation), which in turn can cause piston, ring and head gasket damage. As the internal parts of the engine expand from the excessive heat, clearances may be reduced to the point where metal-to-metal contact occurs. Valve stems may gall and stick, and the pistons and camshaft might scuff or seize.

Severe overheating also creates tremendous thermal stress in the head(s) and block. This, in turn, may lead to cracking and/or warpage. This is a common problem with overhead cam engines that have aluminum heads.

The only vehicle that can be “safely” driven when the temperature warning light on is a late model Cadillac with a Northstar V8 engine. Cadillac engineers designed the engine control system to automatically deactivate half of the engine’s cylinders if it senses an overheating problem. This reduces the heat (and power) being generated by the engine, and it allows the “dead” cylinders to pump air through the engine for internal cooling. The system is designed to provide a “limp-in” mode so the vehicle can be driven to the nearest service facility or Cadillac dealer for repairs. It is not designed for continuous driving.

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