My ABS seems to activate when driving very slowly on my 2013 Ford Edge SEL. Based on this research, I think it may be a faulty ABS sensor. My question is, how can I confirm this? And is this a DIY fix? Thanks. – Puneet L.
False activation is a common problem. It occurs when a single anti-lock braking system (ABS) wheel-speed sensor experiences a sensor/wiring problem, or there is an increase in the gap between the sensor and it’s reluctor ring. On most cars, each of the four-wheel speed sensors produces a small amount of AC voltage. The faster you go, the more voltage is produced. Your vehicle’s ABS control module reads each sensors’ voltage output and compares it with the others. As wheel speed increases and decreases, the amplitude across all four sensors should remain consistent relative to each other.
However, because the amount of voltage being generated by the sensor is so small, a problematic sensor may initially appear only when going slowly. As soon as the amplitude of the troubled sensors falls below its usable threshold owing to slightly higher resistance, the ABS control module won’t be able to detect a signal and incorrectly calculates that the affected wheel has locked up. It then commands the venting of brake pressure to that wheel in an attempt to get the wheel spinning again. If you are really good with a voltmeter you can figure it out as a DIY’er, but for most, this repair is going to require a professional.
I have a 2011 Honda CR-V that makes a loud rattling noise on start up in cold weather. The dealer says it is the VTC actuator and replacing it is a 5-hour job, according to their flat-rate book. The service bulletin from Honda says it’s a 2-hour job. Why the time inflation and is whatever is causing the noise harmful to the long-term health of the engine? Thanks. – Bruce R.
VTC actuators are indeed very common on your generation CRV and I have found that even the corrected Honda replacement part fails sooner than I feel it should. The VTC actuator is contained within the engine timing system and employs oil pressure to advance the engine’s mechanical timing. The rattle comes from lack of oil pressure to the actuator, most noticeable after the vehicle has sat overnight and in colder weather. In many cases, living with the occasional rattle won’t be an issue, however if it makes noise all the time it should be replaced.
The flat-rate time system used in this industry is the primary reason I left the dealer years ago. Thankfully, I haven’t personally worked flat rate in many years. My opinion, albeit dated, is that auto manufacturers feel that their factory-trained technicians should be able to get their repairs done quicker than a general repair shop. Many dealer technicians that work on this flat-rate system will complain that “warranty work” forces them to do their work at half pay. But that is a whole other conversation.
Lou Trottier is owner-operator of All About Imports in Mississauga. Have a question about maintenance and repair? E-mail firstname.lastname@example.org, placing “Lou’s Garage” in the subject line.
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