It’s pretty simple, actually. Jump-N-Carry lithium jump starter models JNC325 and JNC345 are equipped with a DC-out pin jack. It is important to note that, because these models utilize a 4-cell battery design, the DC out voltage is higher than a lead acid power port, in this case 14.6-16V, depending on the unit’s state of charge. This shouldn’t be an issue, but it is important to note. Both models include a DC female power port adapter that plugs into the DC-out port on the jump starter. The operator can then connect our SOLAR ESA30 Memory Saver Connector between the DC female power port adapter and the vehicle’s OBDII port. Since both lithium units have a power button to activate the unit, it is critical in this application to ensure that the unit is powered up before removing the vehicle’s battery.
Like most things in life, using a memory saver connector to turn your jump starter into a vehicle memory saver comes with a few things to keep in mind. So, please read the fine print below.
Prior to connecting the memory saver, verify all vehicle accessories are OFF. To prevent overloading of a vehicle fuse or other vehicle damage, do not use the Memory Saver if the vehicle’s current draw is 4 amps or more when the vehicle is in a KEY OFF condition. Also, vehicle systems often cycle after the vehicle is turned off. Such cycling can place heavy demands on the vehicle’s electrical system. Before connecting the memory saver, turn the vehicle’s key to the OFF position and wait for 25 minutes. Doing so will ensure that all vehicle cycling is completed (most vehicles).
When performing this application, we recommend a specific connection sequence to ensure that your memory saver will effectively perform its task:
- Connect the ESA30 memory saver connector to the jump starter via the DC female adapter included with your JNC lithium jump starter. Power up the jump starter. Confirm a proper power connection by observing the LED light of the ESA30. A lit LED shows power is flowing.
- Disconnect the ESA30 from the jump starter.
- Connect the ESA30 memory saver connector to the vehicle via the OBDII port. Confirm a proper power connection by observing the LED light of the ESA30. A lit LED shows power is flowing from the vehicle.
- Leaving the ESA30 connected to the vehicle, reconnect it to the jump starter. The LED on the ESA30 should still be lit.
- Now, you are ready to change out the vehicle battery.
- Once the new battery is installed, disconnect the jump starter from the vehicle’s OBDII port.
Remember that, when you change out the vehicle’s battery while using a memory saver, the vehicle’s electrical system is still live – that’s the whole point – and all usual care must be taken with the electrical system. To prevent a short circuit and loss of vehicle memory, do not allow the vehicle’s disconnected positive battery cable or the output cables from your jump starter to touch vehicle ground.
Note: Some vehicles, for reasons related to the warnings above, are not compatible with the use of a memory saver connector to connect a jump starter via the OBDII port (BMW X5, some Volvo models, for example). Typically, these vehicles are higher end vehicles with advanced electronics or sophisticated power down routines. On these vehicles, you will often find starting points in the engine compartment (the battery is typically stored in an odd location), which are the manufacturer-preferred connection location for jump starting. These starting points provide a great alternative to connecting via the OBDII port, since, like the OBDII port, they are typically always on and have the added benefit that they are designed to handle high power loads. When using this method, the jump starter positive cable is connected to the vehicle’s positive starting point and the jump starter negative cable is connected to the ground point (if supplied) or a standard engine or chassis ground. This article, by Karl Seyfert in Motor, provides a great example of what can happen when you try to provide memory saver function to a vehicle through the OBDII port when said vehicle does not like that method.