With a digital volt meter.
located passener side in front of battery, bolted to frame,grill
VAN
In a 1997 Ford E250, the negative ground is typically connected to the vehicle's chassis. You can find the negative battery terminal attached to the battery, which is usually located under the hood. The negative cable usually runs from the battery to a grounding point on the engine block or the frame to ensure proper electrical grounding for the vehicle's systems.
Where is the voltage regulator on a 1991 e350
On a 1996 Ford E250 van, the voltage regulator is typically integrated into the alternator. To locate it, you would need to find the alternator, which is mounted on the front of the engine, usually on the driver's side. If the regulator is external, it may be mounted on the firewall or near the battery. Always consult a service manual for precise locations and diagrams.
Pull out the dipstick.
check wiring connections make shure they are tight or that they all got put back on. check for available voltage at starter and batteries also proform voltage drop test on starting circuit
under the passenger door bolted to the frame rail
drivers side by door under van attached to inside of frame
check odb codes and check o2 sen.
Check source for user manual.
Check the underhood sticker or the build tag.