Hi,
Today's technology can be a headache. There is an intelligent battery sensor (IBS) on the battery connection. See pic 1 below. Disconnect that for about a minute and reconnect to see if that resolves the issue.
The IBS has a built-in thermistor that calculates the battery temperature. The microprocessor uses this data to calculate the battery's State of Charge (SOC), internal resistance, charge received, electrical demand, and time in service. This information is reported through the LIN Bus circuit to the Body Control Module (BCM).
What I believe is happening is the BCM thinks the battery is below the threshold, and it's allowing the vehicle to start. If you disconnect the IBS, it should reset to 80% charge.
Try this and let us know if it helps.
Take care,
Joe
See pic below.
Image (Click to make bigger)
Tuesday, May 27th, 2025 AT 8:32 PM
