Watch Those Connections!

Some appliances such as stoves and dryers, do not come with line cords when the appliances are purchased.  As a result, consumers have to make separate purchases in order to use their new machines.  When attaching the cords to the appliance, pay close attention to the way the manufacturer requires that the line cords are connected.  For many do-it-your-selfers, this is no big deal.  It shouldn’t be a big deal for a professional electrician either.  However, we are all human and subject to making mistakes.  Case-in-point: the following dryer fire.  Although minor as residential fires go, the damage could have been much worse.  The photographs shown below illustrate how the manufacturer called for the installation of the line cord and the subsequent way, the cord was connected.

The manufacturer’s schematic drawing shows how the “hot” (red and black wires) lines of the line cord were to be attached to the L1 and L2 terminal block terminals.  The common line or white wire was to be connected to the N terminal on the terminal block.  Lastly, the green wire or earth ground, was to be connected directly to the appliance housing.  The photograph below shows how the white and black wires were reversed on the terminal block.

 

 

Since the common and earth ground points are electrically the same point, the dryer was, in effect, energized through the housing.  Anything in contact with the dryer housing, such as the exhaust duct, will also become energized.  Dryer ventilation ducts are usually coils of steel wire wrapped with a thin layer of vinyl or aluminum material.  As current flows through the steel wire, the external covering is heated.  If not stopped, the heat will cause the covering to melt and possibly ignite.

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Wheel Separation in 2016 Ford Taurus-Possible Recall?

One of our recent investigations involved the separation of the left front wheel and whether it was the cause of a two vehicle accident.  The scenario was such that the driver made a right hand turn and felt the vehicle pull to the left.  The driver also stated that he lost control and hit a parked car.  Typically, in these types of impacts, the wheel is pushed into the wheel well.  But, in this case the wheel separated from the car.  Upon examination, it was determined that the threaded connection holding the strut to the frame was broken as well as the clamping part of the lower steering knuckle.  The failed parts are shown below.

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Failed strut threaded connection

DSC01042Clamping part of lower steering knuckle found broken

It should be noted that the steering arm tie rod was also bent and broken and that a stabilizing rod connected to the strut was separated from its knuckle joint.  If either of these connections is broken, then the wheel will become unstable.  Are there other instances where drivers have experienced similar situations?  Is this a condition that warrants a recall?

Lathe Chuck Injury Due to Faulty Lathe Operation

One of the more interesting cases that we have been assigned had to do with a personal injury suffered as a result of an airborne chuck.  The injury occurred after an individual purchased a chuck and spindle adapter for use with a Shop Smith lathe that was manufactured back in the late 40s or early 50s (see photos below).

 

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Chuck and pin wrench used to tighten chuck onto spindle adapter

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Antique Shop Smith Lathe

After attaching the spindle and mounting the chuck, the owner started the lathe and tested the operation.  Everything went well until the machine was turned off.  As soon as it was, the spindle shaft stopped but the chuck kept spinning and spun itself off the adapter.  The chuck went airborne, bounced off parts of the lathe and hit the owner’s hand causing severe injury.  The investigation came about as a result of the owner’s allegation of a defective product, ie, the chuck was defectively designed and had no means of stopping if it separated from the spindle adapter.  The chuck is designed to be tightened against the spindle adapter using special wrenches.  According to the owner, he claimed that he “tightened the chuck as tight as he could” before starting the lathe.  During the examination of the lathe, the lathe was started and run without the chuck attached.  When the lathe was turned off, it immediately became clear that there was something wrong when the spindle shaft did NOT coast to a stop.  It was also clear that the abrupt stop provided the torque necessary to cause the chuck to spin off the spindle adapter.  In addition, it was also noted that if the chuck was to stay attached to the spindle adapter, the torque applied during tightening had to be greater than the torque causing separation.  After working the math, it was determined that the owner could not have tightened the chuck was much as he claimed.  As a result, it was further determined that the owner unfortunately caused his own injury by ignoring the problem of abrupt stopping of the spindle shaft.  The lawsuit was subsequently dismissed.

Power Steering Recall

Roughly two years ago, Chrysler recalled approximately 442 Dodge Ram pick up trucks for a problem with the electric power steering (EPS) module.  The recall applied specifically to 2015 -2016 Ram 1500 trucks manufactured between January 22, 2015 and September 13, 2015.  The problem had to do with short circuiting of the EPS circuit board that would cause the loss of power steering and increase the risk of a crash.  Since that recall was put in effect, reports have been received that indicate that the short circuit is not enough to cause the 100 amp fuse, that is supposed to protect the module, to open.  As a result, the short circuits are causing wiring to overheat and ignite resulting in vehicular fires.  It should be noted that overheating of the wiring has not been addressed and is not part of the original recall.  The original recall is identified as NHTSA campaign # 16V16700 and Chrysler recall # S19.  A copy of the recall is attached below.  The second page shows a wiring diagram and the connection between the EPS module and battery through the 100 amp fuse that is in question.  Also shown is the connection between the battery and the power center.  If a fire occurs, the origin appears to be in the area of the battery and power center, both of which are located on the driver’s side of the engine compartment above the left front wheel well.  Complaints regarding vehicular fires related to this recall should be reported to NHTSA through their website at www.nhtsa.gov.

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Recall & wiring diagram0002

Toyota Recalls Hybrids

Toyota Motor Corporation has announced the recall of approximately 2.4 million vehicles.  It is estimated that 830,000 vehicles were sold in North America.  These vehicles are gasoline engine hybrids that can stall as a result of a problem with the “failsafe” switch over driving mode.  When the vehicles fail to switch driving modes, a loss of power can occur resulting in a stalled condition.  Although Toyota is not aware of any crashes, an unexpected stall could cause the driver to lose control and crash.  The affected vehicles apply to Prius and Auris models manufactured between October 2008 and November 2014.  For additional information, consumers can contact Toyota by calling 1-800-331-4331.

GM Recalls for Loss of Power Steering

General Motors (GM) has announced that it is recalling 1.2 million pick up trucks and SUVs due to a temporary loss of power steering.  The recall applies to 2015 Chevrolet, GMC and Cadillac vehicles.  When the power steering disappears, the vehicle can become difficult to control increasing the risk of a crash.  GM has received 30 reports of crashes and two injuries.  GM will update the power steering module software free of charge for owners of the recalled vehicles.  For additional information, owners can contact GM by calling 1-866-522-9559.

 

Fire Hazard Prompts Ford to Recall 2 Million F-150s

The National Highway Safety Administration, NHTSA, has announced that Ford has recalled approximately 2 million F-150 pick up trucks.  The recall applies to 2015 -2018 F-150 regular and super crew cab pick up trucks.  The seatbelt pretensioner can generate sparks when activated during a sudden stop.  The sparks can ignite flammable material located inside the “B” pillar post including carpeting and insulation.  Ford has also identified the manufacturers of the seatbelts.  Joyson supplied the seatbelts for the 2015 to 2017 models while ZF supplied the belts for the 2018 year models.  Approximately 1.62 million vehicles were sold in the United States, 340,000 vehicles were sold in Canada and 37,000 were sold in Mexico.  The recall is expected to begin on September 24, 2018 with Ford notifying owners.  The Ford recall identification number for this recall is 18S27.  NHTSA’s campaign number is 18V568000.  For additional information, consumers can contact Ford by calling 1-866-436-7332 or visiting Ford’s website at www.ford.com.

 

 

 

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