Phillips Industries has introduced what it calls the cure for the most common warranty complaint with 7-way tractor-to-trailer electrical connections -- complete loss of electrical function on the “blue” circuit.

The loss of function almost always results from lack of maintenance, water and chemical de-icer intrusion into the connector. Phillips' newest product innovation, the patented Sta-Dry QCMS2 (Quick Connect Modular System), prevents water intrusion and eliminate corrosion of the connector pins.

In researching the warrant follow-ups, Phillips noticed that the failures almost always occurred at the tractor union, and much less frequently with the trailer connector. The constant power circuit, the blue wire on the number 7 pin always shows the worst corrosion because that circuit is always powered.

Since the SAE J560 standards do not call for a watertight connection, and with many connectors being constructed in different sizes for compatibility purposes, it leaves a gap of up to 3 mm or more between the plug and socket connection where contaminants can easily enter.

"Fleet maintenance experts say the 7-way union on the tractor side is disconnected and cleaned 99% less than the trailer 7-way union," says Megan Vincent of Phillips Marketing. "Combined, the gap in the connection, little or no proper maintenance and the inevitable water intrusion create a recipe for corrosion."

Phillips' new modular socket/plug hybrid, the QCMS2 is semi-hardwired to the tractor creating a complete seal at the 7-way connection. By removing the socket from the union, the QCMS2 mates directly with Phillips STA-DRY QCS (Quick Connect Socket) boot, eliminating any gap where moisture can enter.

Phillips tested the Sta-Dry QCMS2 mated with a Sta-Dry QCS socket in their electrified salt brine tank for 120 hours, exposing samples to a continuous spray of brine solution through an irrigation system while electrical currents pass through the product. This test reproduces field results showing corrosion at 120 hours on traditional J560 designs. Phillips' test data shows the QCMS2 and the QCS2 remain corrosion free and without water intrusion under the same conditions.