Wednesday, January 02, 2008

Thomas Buses HDX Electrical Panel

Thomas Buses have changed through the years and one model with a different electrical layout is the HDX. This 2004 has everything in a totally different layout compared to the Saf-T-Liner.

The Body Electrical [lights and accessories] Schematic is nicely displayed on the side door panel below the driver's side window.

[Click On Each Photo To Enlarge]

The circuit board shown here has been unfastened and tipped downward so you can see the many connectors that hook up with relays and battery supply junctions. There are 3 circuit boards in total with specific spots for each connector.

The circuit board is upright once again [located in the side panel] Here you can see the main battery power supply on the left with the many fuses and relays required to run lights, heater motors, solenoids etc.
The LED lights above indicate which relays are active, YELLOW
indicates the relay coil has been activated while the GREEN LED indicates the circuit is connected to the load.

Thomas Buses have evolved from the basic "battery to load with a switch in between" to complex relays & mult-functional switches that handle the demand for more circuits that can meet the load & safety component demands of today's School Buses.


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John said...

A little Help? Can anyone identify the white 12 and 8 pin connectors(4 connectors accross, the 3rd partially covered by label) plugged downward into the circuit board in the 3rd picture directly above the date stamp?

Thanks to all.

John said...

On above comment, any ideas or info can be sent to me.

Thanks again...