[H20DOG]

Sunday Compass did not want to start. Acted like a low battery, starter barely turned over the engine. Voltage was 11.9 and 12.0 volts showing on the gauge. After several tries and having to pump the gas pedal it started. Voltage was then showing as 14.7 volts indicating that the battery was pulling hard charge from the alternator. Let it run for an hour and shut off. Voltage was then 12.8 volts. Went to AutoZone and had charging system checked. They said battery was good and charging system was good. All seemed well on way home and in driveway.

This morning, I went to start the Compass for my wife to go to work. First hit the start button without trying to start so I could check the battery voltage on the dash. 12.6 volts. Jeep started no problem. Voice came on saying something about "unable to complete something, no phone connected/paired. Please see settings." Voltage was then only reading 12.6 volts instead of the normal 13.8 - 14.4 volt range indicating that the alternator was not working and the car running strictly on the battery. I popped the hood and checked the voltage with a meter and it also read 12.6 volts. Turned car off and restarted while watching the volt meter on the dash. It started at 13.8 volts and fell to 12.6 volts. I tried this a couple times with repeated results and shut off the car. Couldn't let the wife try to drive to work like that. Her daily commute is 142 miles.
After I got cleaned up I drove the car to Walker Jeep Ram dealer 3.2 miles away. On the way there I kept a close eye on the voltometer in the dash. Once while going down a hill when I let off the gas the voltage started reading 14.7 and started falling before returning to 12.3 volts when I gave it the gas. I let off the gas to see if voltage returned but no. Then while turning right at the next intersection volts went back up to 13.2 volts again without giving any throttle before going to 12.3 volts. Then a few seconds later back to 13.2 volts for a split second before staying at 12.3-12.1 the remainder of the drive.
Dealership was packed and said they were booked into next week. I informed them that the Compass was our only vehicle and that my wife needed to get to work so I asked for a loaner. Dealership said they had no loaners available after first asking if I bought it there (which I had not). Shuttle van took me home.
I will update later as the dealership just called and said it was ready and was sending the shuttle to pick me up.😀

 

[H20DOG]

Went to pickup the Compass from the dealership. They said they couldn't find anything wrong with it but did do an update on the BCM. I got in the car. Checked voltage before and after starting It. Voltage hits 13.7 volts for a breif second after starting then drops to battery voltage of 12.6 volts. Went back into dealership informed service department that it was still not fixed and wanted to show them. Then had me pull it around and back inside where I then tried to show them. They claimed nothing wrong and that the car is designed to do that, "These new cars aren't like the old ones." They couldn't have spoken a more true statement. I then asked them" Does the cars no longer have voltage regulators or the computer control the voltage? They said yes, but.....and couldn't finish the answer. They then asked if I wanted to leave it overnight. I said, "No", because thinking if they were that inept I would rather try taking it to a different dealership.

Drove it home. Several times after hitting the brakes the alternator/voltage regulator would kick in an out the proper voltage until I hit the gas pedal.

Anyone have any ideas what's up? Car only has 33,000 miles on the odometer. 2019 Jeep Compass 4x4 Sport model 6 speed manual.

 

[H20DOG]

Most of the cars I've had that even had a gauge didn't give you quantity. As long as it stayed slightly to the charge side I was happy and so was the vehicle. Ours is a 12V system -- that would be the center point of a conventional gauge -- so anything over that means it's charging. A lot or a little doesn't matter to me as long as it starts in the morning.

Those cars must have had an amameter not voltameters. In years past, many American auto manufacturers installed amameters instead of voltameters. But starting in the late '70s (?) they started switching to installing voltameters. Occasionally, a vehicle would/will have both which is the best setup because they show different things. Anymore we are lucky to have either as the manufacturers know most Americans (I can't testify regarding other country's citizens) don't even have a clue to look at either type of guage much less know what the data means.

For those interested
Amameters are wired in series to the system and indicate whether the system is consuming more amps than produced 😡(left of the zero centerline), producing more amps than consumed 🙂(right of zero centerline), or equal amounts of consumed and produced amps 🙄(zero centerline). OEM amameters normally didn't show numbers.

Voltameters are wired in parallel to the system and indicate how many volts the system is generating. If the vehicle is not running, it will indicate the total combined voltage of the battery plus any residual voltage from capacitance that may be in the system less any resistance of the system. If the vehicle is running and the alternator and voltage regulator system is performing correctly, it will indicate the voltage output of those two components. Most voltameters show numbers.

 

[H20DOG]

So where are the numbers on my oil temperature gauge? If ever there was a useless invention!

Sometimes it's difficult to find a practical use for a gauge. Maybe they should put detailed gradients on the oil temperature gauge and measure it in some obscure scale (like Rankine) that would mean nothing to the average driver.

I wish they would let us select which and what type of guages are displayed on the dash.
I somewhat agree about the oil temp gauge. Transmission temp would be more useful but why not have both.

I had a car years ago that overheated and warped the intake and head. Coolant sensor was located in the highest part of cooling system so when the coolant started leaking out it read the air temperature inside the cooling system. The temperature indicated lagged behind the engine (oil) temperature.

 

[H20DOG]

My sister in law just experienced this exact same problem on her 2022 Jeep Compass. 600 miles on the odometer and her vehicle would shut off on the road. Message would pop up "Stop Safely Vehicle Will Shut Off Soon".

Better check the oil level. That's the message displayed before shutting down due to low oil.