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Hybrid & Beyond

Tuesday 28th February 2017
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In the past, it was normal practice to accept any job that came into the workshop, as cars had very similar systems. Once you knew the basics, you could get by with a little help from your technical manuals and data software. But this is no longer true.
    A recent case we had with a Smart MHD non-start intermittently. This 2009 Smart car MHD came into a workshop with little or no knowledge of hybrid systems. The technician with 30 years workshop experience, suspected a starter motor fault as he could hear a slight noise from the engine when cranking.
    Heo proceeded to unplug what he thought was the starter motor to test power and grounds during cranking, but there were some odd voltages present and too many wires present in the connector. After calling the helpline for wiring information on the starting system we told him it was a Micro Hybrid with an uprated Alternator/Starter system. And what he had disconnected was the transmission selector motor. Now he had faults in the gearbox system that needed to be readapted and reset.
    After some checks, it was found the battery was the fault, as it was the original battery from 2009. A new battery was installedy the correct AGM type for this Micro Hybrid system. Resetting the power management module and all was well.

System Knowledge    
    Hybrid systems are now coming in various types. Apart from 12 volt systems, there are new systems employing voltages from 48-volt high power alternator/starter systems, equipped with Lithium-ion batteries with plug-in charging, up to more common battery voltages of 200 to 400 volts DC, with outputs up to 650 volts AC after Inverter/transformer intervention. These can Be Strong Hybrid or EV systems not forgetting PHEV, and range Extended EV  vehicles.
    These systems are now so powerful correct knowledge of safe handling is now of paramount importance: It is worth noting an electric shock above 60 volts is considered fatal requiring only 250 milliamps DC to be fatal. Or 30 milliamps for AC.
    It can look quite innocent to most inexperienced mechanics, but these systems are unforgiving if not handled correctly. Even if working on so called safe components, be aware of components such as AC compressors or power steering systems, that can be AC or DC powered with high voltages.
    Even for a simple task of jacking up a vehicle, system knowledge comes into play. Where is the battery pack located? PHEV and EV vehicles can have the battery module under the vehicle spreading out over most of the chassis area, Jacking up on a battery module can ruin your day in many ways.
    Here is a useful site for safety information when dealing with electrified vehicles:

    The IMI are now reviewing the EV training they offer to include all system types and have 4 levels of qualifications covering basic safety for drivers, to advanced knowledge for mechanics removing and repairing systems.
    The future is here now.
    Join our growing team of members today, who all have access to 1000’s of answers to tech questions on demand. Call us now on 01-905-9500 to join or for more information.