priority start

[vjls]

I told the shop to by pass that second battery like you guys suggested well this is what they did. they had it 2 weeks they swear it was cranking amt everday

well tried to start Monday nope had to jump start fired right up called shop they basically did not want to talk about it said I must hVE left something on nope did not today Friday all it did was click we had to jump start again

took a picture of this Monday light was not on today it is I google it but I really did not understand. any of ypu guys want to explain it to me as you guys are really great at that

thank you

[Sugarcube]

I'm not sure what you are asking but the red light on the priority start means that your battery drained to 11.7 volts. So the priority start is engaged and has turned off all battery power, like it is supposed to. This is to preserve enough battery power to start the engine. When the red light is on, turn on the headlights or press the brake and then immediately try to start the car. When it starts take it for a long drive to recharge the battery. When the battery is charged enough, that light will turn to green and the priority start will start monitoring the battery power again.

Eta: If you see no light at all, It is either not connected properly, the battery is dead, or the priority start is malfunctioning and needs to be replaced.

[vjls]

you summed it great perfect now Monday I will know what to look for fyi did not crank Friday we had to jump sTART it and priorty is brand new they just put it on thank you

they put that on as the second battery under the van was gone I told them to by pass it wire direct they did not put the prority on and then did not explain what they did or how it worked.

thank you again

[Rononwheels]

I may be late to this post.... But I have had Ford vans with the factory auxiliary battery mounted under the passenger side doors.
As it comes from the factory, it is NOT wired to anything, it is for adding stuff... It has a relay that connects it to the main battery
for charging when the engine is running, and it disconnects when not running.

If your van was a diesel engine, both batteries would be connected together...

That "priority start" sure dosent look new to me?? Or maybe they drug it around in dirt before they installed it?

you summed it great perfect now Monday I will know what to look for fyi did not crank Friday we had to jump sTART it and priorty is brand new they just put it on thank you

they put that on as the second battery under the van was gone I told them to by pass it wire direct they did not put the prority on and then did not explain what they did or how it worked.

thank you again

[Gearhead]

The "Priority Start" should prevent battery from going so low that it won't spin starter. However, EFI/ECM needs a certain level of volts to work. Meaning engine may turn over but ECM won't trigger fuel injectors in some cases.

Back in the days when I helped build many highly valuable (to the owner) street rods and vintage classic cars, many of them had a manual battery disconnect switch. It's main intent was as a second hurdle a thief would have to know about to steal the vehicle. On many vehicles like Corvettes (which had an inherent drain) that sat for long periods, these type switches would completely disconnect battery and eliminate it from any vehicle drain. The down side, clock and radio presets (or any other component with memory) will be lost each time you disconnect. . These are manual disconnects so would require someone to disengage or re-engage the battery each time. If, after installing such switch and your battery no longer goes dead, that would indicate your vehicle has a drain. The below link is just an example of a quick search.
Scroll up and down the page and you'll see the different types available.
https://www.amazon.com/Universal-Dis...ustomerReviews