Battery replacement help!

[sharpsicle]

Didn’t mean to offend. I just don’t see the need for more than one battery and such a wonky procedure to replace it/them. I’m a Jeep fan with currently an Ecodiesel, Pentastar, and an ETorque. I was just expecting the Ecodiesel to actually keep running once leaving town. I guess I was asking too much. It’s just that my old ‘77 Benz with over 350,000 miles still hasn’t needed a major wrench on it. I thought that we’d be doing better by now.

I know everyone hear loves to do it, but you can't take an individual case and say it's an example of the whole of manufacturing and design. We are doing better now. Sorry you're having problems, but I'm a firm believer of making educated decisions on specific situations rather than sweeping generalizations on incorrect information.

Sponsored

 

[ShadowsPapa]

N1 and N2 should be the same. If N3 has a lower reading than N1 and N2, my guess is that the N3 fuse is open. You are reading the values of batteries separated by the open N3 fuse. Another possible explanation for the difference in voltages is the PCR relay circuit is open. I would separate the grounds at the IBS again, charge both batteries.

It might help removing the fender ground and making it the last connection.

Yes. It won't show until that battery doesn't stay charged, or unless you measure voltages.
If that N3 fuse was good, it would be a direct connection to the buss that ties them all together and the voltage should be the same. Any that are lower could indicate a blown N3.
The voltage at N3 could be lower due to a voltage drop over the wire from the aux + terminal, through the cable to the PCR, through the PCR and back up to N3
N2, 3, 4, 5 and 6 should all read identical if the engine is off and the truck at rest because they all connect directly to the high current fuse buss - unless one is blown, then the voltage is seen through another, longer, path.

As for the complexity - I guess I'm a bit prejudiced because I'm so very used to electric work and know how things like batteries, charging systems and other things work and give me a schematic and some odds and ends info and I'll have it figured out.
I don't know CAN or LIN, but I could learn because I handled Ethernet switching and routing in a former life.
When people try to compare reliability, how soon they forget the 10,000 miles tune-ups, points, condensers, timing lights and dwell meters and plugged up carburetor circuits, sticking automatic chokes, stuck heat riser valves, plugged cross-over passages in V8 intakes leading to cold drivability issues, plugged gas tank "socks", ruptured fuel pump diaphragms dumping raw gas into the crankcase, errant spark causing the dipstick to shoot up with enough force to dent a hood, points rubbing block wearing increasing dwell but retarding timing, other fun stuff. I could go on and on about the stuff I saw over the years.......... the number of Ford vehicles or others running Ford ignition systems that stopped on the interstate because the control box got hot. Let it cool, or shoot some R12 at it, and it would start again. We used to stock a half dozen of those parts at all times. Or the GM HEI pickup coil leads that broke from flexing due to the vacuum advance operation. It might start and run - then vacuum advance moved the coil and the engine died or misfired badly. Or the Prestolite vacuum advance devices that ruptured and allowed air/fuel mix from the intake manifold to get into the distributor and the cap would blow clean off the distributor.

 

[McQueen21]

N3 isn't the "start stop fuse". It's the fuse to charge the aux battery via the alternator.
If you fully charged both batteries, even if the N3 was blown you'd not know it for a while as the battery would have a full charge. The N3 being blown would only be noticed after some stop/start cycles taking power from the aux battery.
Do you have 12.7 volts at N1 - the one closest to the front of the truck?

N4 is power to the PDC, make sure that's hot.
N5 is the cooling fan (not a concern yet) and N6 is the EHPS or the electro-hydraulic power steering pump (not a concern yet)

Thanks for your help, I have read a couple of your other responses you are very helpful. I am still trouble shooting no crank issue. I pulled the fuse array and tested it all where good. Now I am going to check the couple of relays and fuses for the starter and ess. I am determine to figure this out.
Do you know how to test the IBS?
Thanks for

Sponsored