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Keith Littleton

President, K&D Technical Innovations

Keith E. Littleton is president of K&D Technical Innovations, a service provider offering training solutions for industry and education. Littleton specializes in CAN communication issues and lab scope diagnostics, and is the current Station Chair for TMC SuperTech’s electrical test station. Littleton holds numerous ASE certifications, as well as nine Toyota certifications and 11 GM certifications.

Image courtesy of K&D Technical Innovations
Fig. 2: In the training provided by K&D Technical Innovations, there is a test that technicians can do using a multimeter with a fast-enough sample rate to capture the high voltage created when the coil in a relay is turned off.
Battery & Electrical

What is a bistable relay?

Dec. 3, 2019
Even if you’ve never heard of bistable relays, you have likely diagnosed circuits affected by them.
Image courtesy of K&D Technical Innovations
This pattern shows the voltage and amperage for an injector with normal open/close time.
Diagnostic & Repair

Making a case for oscilloscopes

May 11, 2018
Utilizing an oscilloscope during diagnostic vehicle testing can help make technicians more efficient at diagnosing electrical issues.
Photo courtesy of K&D Technical Innovations
The above relays appear to be the same, but they are not. These relays will fit in both applications and will operate the circuit in the same way. The difference is one of the relays has a diode for voltage spike suppression and the other does not. It is very easy for a technician to install the incorrect relay during a repair or in troubleshooting.
Diagnostic & Repair

How to avoid voltage spikes when replacing relays during truck diagnosis

March 12, 2018
Often seen as a quick fix, using the wrong relay for the application can cause inadvertent voltage spikes.