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Updated: 25 May 2024
HONDA ► 23 units
NISSAN ► 12 units
TOYOTA ► 16 units
SUZUKI ► 1 units
MITSUBISHI ► 1 units



Advanced Vehicle Security



* Securing The Past, The Present & The Future *

Engine Guardian Watchdog TM4
Engine Temperature Sensor & Overheating Alarm

The TM4 is the best all round hot engine temperature & low coolant alarm on the market.

It can quickly detect ALL causes of engine overheating, including coolant leaks, sticky engine thermostats, engine water pump leaks, coolant blockages, radiator blockages, faulty radiator caps & even heat build-up from engine oil problems. Because it is so accurate, it can even detect if your engine cooling system is becoming inefficient.

TM4 displays your exact engine temperature and alarms with a WARNING LIGHT & LOUD BUZZER if your engine overheats for any reason.

The Engine Watchdog TM4 is the No.1 selling Engine Protection Alarm for good reason:-

  • TM4's uses the most reliable monitoring method

    The TM4's electronic "East Fit" heat sensor simply fits like a washer under any suitable bolt that is near the heat source. Here it monitors the engines metal temperature right where major engine damage occurs. By directly monitoring the engine cylinder head and engine block temperature, ALL engine overheating causes are instantly detected. This includes problems low water alarm sensors can not detect such as blockages and circulation problems.

    The TM4's electronic sensor also overcomes the problem conventional engine temp gauges have of becoming inaccurate once their sensor looses contact with coolant. With a TM4 you will always know your true engine temperature range in any situation.

    This method of heat detection is highly reliable because heat transfers rapidly and evenly from the inside of the motor to the outside (air cooled engines rely on this principle). You will be amazed at the speed the TM4 works, for the first time you see your motor temperature rapidly rising and falling moment to moment as you drive under varying loads and traffic conditions.

  • You can program the TM4's alarm sensitivity to suit your engine

    The TM4's audible temperature alarm can be set anywhere from 1 to 125 degrees Celsius by using the "Set Alarm" button on the front panel (model TM4 is set from 34 to 255 degrees F in two degree increments). This means to install a TM4 you don"t even need to know your engine"s temperature range. You simply watch the TM4 and note the highest temperature your engine reaches during normal driving. Then you set the audible warning alarm to go off at a slightly higher temperature, it's no harder than setting an alarm clock and will alert you before your dash temperature gauge has even moved.

  • The TM4's sensor cannot cause engine coolant system leaks or void the engine"s warranty

    The TM4 is perfectly safe to fit because it does not require you to break into the vehicle"s cooling system in any way. It cannot be the cause of coolant leaks in the future and because you are not interfering with the engines internal workings in any way, the TM4 will not void the warranty on new or reconditioned engines.

  • The TM4 can detect engine cooling system inefficiencies

    As cooling systems age they often become less efficient and the highest normal operating temperature starts to creep up. Because most conventional dash gauges have a 'flat spot' around the normal mark, these small increases are not detectable. It is only when the engine is suddenly worked hard, such as when towing, that cooling system problems become evident. Only a TM4 has the sensitivity and accuracy required to detect these slow temperature increases and alert you to potential engine overheating problems.

  • TM4 also has an option to turn your existing engine oil pressure warning light, into an "Audible Warning Light"

    TM4 comes standard with an optional wire that can be simply tagged to the engine"s existing oil light switch. If you see the dashboard oil light on, you will also hear the TM4 internal buzzer. (Not for oil gauges)