We test on site using professional charging system diagnostic equipment. The test measures battery state of health, cold cranking amp capacity versus rated spec, alternator output, and whether the battery holds charge under load. If results confirm failure, we recommend replacement. If the battery passes, we tell you that and no replacement is needed.

Yes. On-site battery replacement in the ferry lane is the fastest and least disruptive resolution when the test confirms the battery has failed -- significantly faster than tow extraction. We test first and replace only when confirmed. For most common makes and models we carry the correct replacement battery on the truck.

Yes. Mobile battery replacement comes to wherever your vehicle is -- ferry holding lane, SR-525, Lighthouse park, residential driveway, or anywhere in Mukilteo. We carry the correct battery for most common makes and models on the truck.

Yes. A failing alternator will drain any battery because the battery is not being recharged while the engine runs. This is why we test alternator output on every battery call. If the alternator is the issue, we tell you before replacing the battery.

For most standard vehicles the full process -- testing, confirming the diagnosis, and installing the replacement -- takes between 20 and 40 minutes at your location. In the ferry holding lane we work as efficiently as possible given the urgency of the situation.

The ferry queue creates a cold-soak pattern that is hard on batteries. Vehicles sit with the engine off for 30 to 90 minutes in cold or cool weather -- the battery is not being recharged during this period and continues to discharge from parasitic electronic draws. Batteries that are already below optimal capacity fail to restart the engine when the queue finally moves. The longer and colder the wait, the more severe the discharge.

We carry batteries from reputable manufacturers sized for the most common vehicle makes and models we encounter in Mukilteo including the AWD trucks and crossovers common among Whidbey Island ferry commuters. Give us your vehicle year, make, and model when you call and we confirm before dispatch.