((( Audible))) Engine Temperature & Low Oil Pressure Alarm

Ideal engine protection for all moving vehicles

Air or water cooled

3 MODELS AVAILABLE for Cars, Trucks, Bikes, Tractors & Machinery (see below)


The TM4 accurately displays engine temperature and alarms with a Warning light, Loud buzzer & Display messages if engine overheating or low oil pressure is detected.

Plus the TM4 Single Sensor model can control a Cooling Fan Relay

The TM4 is ideal for alarming Engines, Gear boxes, Transmissions, Transfer boxes, Pumps, in fact any thing that operates between 1 to 125 degrees Celsius (33 to 255 F - see TM2F in options).

Display Functions and Alarm Messages:

The TM4 has a white LCD screen with an automatic back light so it blends into both old and new dash boards alike. It is easy to read in either bright sunshine or at night. All functions and alarms on the TM4 are accompanied by individual display messages so you are never in doubt as to what's going on. The TM4 has up to 14 different display messages, including advanced messages such as 'Sensor Not Connected' should the sensor cable be cut.

Temperature Warning Alarm:

The Engine Watchdog TM4 offers the best all round early warning engine overheating protection available. The TM4's advanced electronic 'EASY FIT' heat sensor monitors the actual metal temperature of the engine, this way ALL causes of overheating are quickly detected before damage can occur.

The sensor fits like a washer under any convenient bolt on the engine that is near the heat source, here it rapidly detects the slightest changes in engine temperature. The TM4's warning alarm sensitivity can be set to suit your individual engine and needs.

The alarm is set by firstly observing the engines highest normal running temperature on the TM4's monitor. Then the alarm is set to a higher temperature by using the push button on the front. Typically the alarm is set to between 5 and 10 degrees above the engines normal running temperature, this usually equates to the warning buzzer sounding at just one or two needle widths above the normal mark on most car temperature gauges.

Because you're not breaking into the cooling system, the TM4 is the quickest, easiest and safest system on the market. The TM4 will not void engine warranty and can be easily fitted by a home handyman.

Oil Light Warning Alarm:

The TM4 can turn a vehicles oil light into an Audible Oil alarm. By connecting the TM4's oil wire to the existing oil light switch, whenever the oil light comes on the alarm will sound and the 'Low Oil' message will display. When starting the engine the TM4 will display 'Alarm Delay On', this gives the driver 10 seconds to start the engine before the oil alarm is activated (if the oil wire is not connected to the oil sender the above messages & alarms will not be apparent and the TM4 will just function as an overheating alarm).

NOTE This feature is not compatible with oil gauge sensors. If you only have a oil gauge and want the oil alarm feature, fit an inexpensive oil light switch to the engine - Standard car type - normally closed contacts, open on pressure.


1. TM4 Single Sensor Single heat sensor version for monitoring the Engine Temperature, Low Oil Pressure and controlling a Cooling Fan Relay. If you USE the relay it will only suit 12v vehicles, without the relay either 12v or 24volts is okay (NOTE: Lots of people buy this unit just to get the display wording and don't plug the supplied Relay Kit in).


2. TM4 Twin Sensor model for Vehicles monitors and alarms both the Engine and Transmission Temperatures at the same time, order model TM4-Twin-Vehicle. (NOTE: The Cooling Fan Relay option is not compatible with this model)


3. TM4 Twin Custom. The display messages on the TM4 twin models can be customized to your personal needs for a small surcharge - maximum of 4 characters per line, for example - Auto on the top line for Automatic & T/C on the second line for Transfer Case. (Note: The Cooling Fan Relay kit is not compatible with this model)



Fahrenheit readout is available, see Specifications and choose Model TM4F when ordering.


The TM4 One and Two sensor models include - The 'Easy Fit' heat sensor & cable, blue oil wire (which is optional as to whether you connect it to your engine), loud internal buzzer, automatic back light, cigarette lighter power plug, under dash tabbed lid (fitted), also supplied in the packet is a second free No Tab lid for on dash mounting, installation kit & FREE postage in Australia.

TM4 One Sensor model also includes the cooling fan relay kit

TM4 has a number of options, see the side bar for OPTIONS .












Cooling Fan Over-ride relay kit only suits the Single Sensor TM4 Model: The suppied relay kit can control an electric cooling fan. Both the ON & OFF temps can be set anywhere from 1-127 degrees C. (Fahrenheit version - 33-255 F in 2 degree increments). The Fan temperature settings are fully independent from the main alarm temperature setting. NOTE: COOLING FAN RELAY KITS ARE NOT COMPATIBLE WITH THE TWO SENSOR MODEL: TM4-TWIN


Mini Sirens: The siren is very loud and for outside use. Both the interal buzzer and siren alarm togehter. (If you want this feature the unit should be run off 12 volts only).

Fahrenheit Version Unit: Reads in two degree increments from 34 to 255 degrees F. CLICK 'TM4F' ON ORDER PAGE

Longer sensor leads are available for machinery: A small charge apply's for longer sensor leads. SPECIFY LENGTH REQUIRED ON ORDER PAGE

Lid without mounting tabs. Standard units come with 12mm tabs on the sides for under dash mounting and a second NoTab lid is also suppied loose. You can request them to be fitted the other way around when ordering.



Compact Size: Face is W 82 mm x H 30 mm. Depth back is 60 mm. A standard lid with mounting tabs adds 12 mm to each end.

Max operating Temp: 127 degrees Celsius or 255 Fahrenheit. Fahrenheit version is available.

Alarm Temp: Adjustable by pressing the front push button. Can be set to alarm at any temperature between 1 to 127 degrees Celsius. (TM2F is adjustable from 34 to 255 degrees Fahrenheit in two degree increments)

Alarm Volume: Internal alarm 85db, plenty for most situations. A very loud mini siren for outside use is available.

Sensor wire length: Standard is 4m (13ft.) Longer leads are available for machinery.

Power: Suits 12 or 24 volt systems. Current consumption without alarms on is 15mA. NOTE if using the Single Sensor TM4 with the Relay plugged-in then use 12volts only.