Knorr's European technical manager for trailer applications is Colin Ross,
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who raises an important point about ABS and EBS systems in general: how are tractor and trailer to be connected? All modern ABS-equipped tractors are already equipped with the 1507638 connector that was developed in the 1980s to power the then-new trailer ABS systems. ABS systems can operate by default using the 24N supply, but the full EBS systems demand a continuous electrical supply, provided by the 1503731(24S) connector or, better still, the 1S07638 connector, which incorporates connections for ECU and CAN links. However, Knorr's TEBS4 module has a failsafe mode so that even if the constant supply fails, the stop-lamp supply will still power basic ABS functions.
A recent survey in Holland found that 60% of trucks did not have their 1507638 lead connected. Ross says, "Operators must start using the connector to get the full functionality of [ABS] braking". He also asks, 'Why isn't the connector hardwired into the truck?" rather than being a separate, easily-stolen extra.