Technical Electrical Issue / is it the Alternator

[BlackForest]

Hi there,

I got hit again: Seemingly unrelated error codes do pop up.

Context:
Fiat Fiorino MKIII (225 from 2021);
car runs like a charm, no probs!

Description:
A. Dashboard warnings
A1. No Start-Stop (and indeed it doesn't work)
A2. No Hillholder (did not verify, but assume, that it doesn't work)
A3. No ESC (did not verify, but assume, that it doesn't work)
A4. No Park Control (and indeed it doesn't work)
A5. Far Controlare Motore (did do so, but garagist had no clue)

B. Dysfunctionalities without Dashboard Warning
B.1. Cruising Light works, if I try to switch to Beam, blue indicator indicates, but the the light is effectively switched of => complete darkness.
B.2. No "Beep" when switching to reverse gear, no reverse camera.
B.3. No Traction Control
B.4. No Cruise Control

C. Warnings, retrieved with MultiecuScan (current edition 5.3)

Code	Message	Source
P0504-67	Brake switch A/B match - Signal incorrect after event	Engine / ECM
P0645-11	A/C Clutch Relay (1) - Short circuit to ground	Engine / ECM
P1612-11	Chain of ECM-IMMU	Engine / ECM
P065A-68	Generator System Performance	Engine / ECM
P2264-67	Water in fuel filter sensor - Signal incorrect after event	Engine / ECM
U1734-87	Battery sensor (IBS) - Missing message	BCM
B1010-67	Brake pedal switch - Signal incorrect after event	BCM
P065A-68	Intelligent alternator (IAM) - Event information	BCM
B1025-14	High-beam lights command - Short to ground or open circuit	BCM
C1215-29	Brake pedal switch - Signal invalid	ABS/BSM

D. Action taken so far
New battery => to no avail!

E. Testprocedures with MultiecuScan
E.1. ABS all the relais successfully tested, i.e. no error and an auditable click
E.2. ABS pump can be switched on and off and is working accordingly

F. Parameters observed
ECU Engine
Battery Voltage: 13,48V (reported as on the pins)
IBS: 71% (loads when motor is running, after 100miles on the motorway it is up to (only?) 82%

ABS
Battery Voltage: 0,138V (reported as on the pins); to be verified, might be a comma shift by the scaling factor choosen in graph

ECU Delphi (Body Computer)
Battery Voltage: 13,92V (reported as on the pins)

Parking Control
Battery Voltage: 13,67V (reported as on the pins)

Battery, measured with engine running: 12,8V
Edit: The voltage varies; after several restarts in a row, voltage goes up between 13,8V and 14,2V. This seems fine.

Any guess, as wild as it might be, welcome! Same is valid for recommendations for further action! Garagist want's to change Alternator.

Edit:
- Did check the lights of the hook. Everything is fine except the reversing light, which is out of function.
- Did activate the actuator for the Beam from within MultiecuScan. Works as expected.
- Break Pedal Switch is reacting (according to MultiecuScan) as expected.
Edit2025-08-06-2002:
- Did check all of the fuses.
- Did attach the dtcscan from MultiecuScan


Tx & Cheers,
BlackForest
Edit: Anybody has a wiring diagram at hand, so that I can see what the defaultiv devices have in common?

 

[BlackForest]

Gotcha!
The culprit was the cable running from the monitor to the reverse camera.

I found that the fuse F51 - which does not show up in any documentation available to me and is also not listed in the user manual -, which is of 7,5A, was dead. On replacing it it did die again immediately. When replaced with one of 10A, all the errors (see prior posting) did disappear. But the reverse camera did not work. And the cables got somewhat warm.

So I did check the whole wiring and finally found the place where the plus-cable running from the camera to the monitor was blank. Nothing to see from the outside (it is shielded and in a protection tube). Did do several cuts to measure the resistance from plus to earth and guesstimate the location. It was next to the drivers seat.

Edit: Just to make it clear let me state, that the fuse I use now is again the original 7,5A.

 

[ZaphodB]

Well done