Possible causes

– Low battery charge
– Battery defective
– Loose or missing alternator drive belt
– Faulty alternator
– Open or short system voltage circuit

Tech notes

Start by recharging or replacing the battery.

When is the code detected?

The electrical system voltage level is monitored for intended voltage level

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)
– Slow engine start
– Low battery power

P0561 JEEP Description

The battery supplies electricity to the Engine Control Module (ECM) even when the ignition switch is OFF. This electricity allows the ECM to store data such as Detected Trouble Code (DTC) history, freeze frame data, fuel trim values and other data. If the battery voltage falls below a minimum level, the ECM will conclude that there is a fault in the power supply circuit. The next time the engine starts, the ECM will turn on the Malfunction Indicator Light (MIL) and a DTC will be set.