B1601 15 BSI Error code

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B1601 15 BSI Error code

Post by TiberGt »

The "Electrical circuit failed: have your vehicle repaired" error pops up every time I start/turn the ignition on.

I ran a diagnosis with Diagbox and I get: B1601 15 -> Central power switch positive (+CPC) relay control fault.

I own a Peugeot 508 hybrid 2012 ( 200 Horsepower model ).

Today I got some mechanics to try and fix the radiator fan since it's not working.
They tracked down the issue, suggesting I should replace the fuse box located near the battery because they say there's a relay there that's not working as it should.
So, they must have broken something in there.

I tried deleting the errors 3 times with DiagBox and also did a battery reset procedure.
What's wrong and what can I do to fix it?

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Re: B1601 15 BSI Error code

Post by GiveMeABreak »

Here is the fault descriptor for this code, but post up your VIN (automasked on post submission) so I can check this is the same for your vehicle, just to make sure.
Fault Code: B1601 15
Description of Fault: Central power switch positive (+CPC) relay control fault : Open circuit or short circuit to the plus. The control is active even though the control copy is inactive. The control line of the central power switch positive (+CPC) relay is considered active when its voltage is lower than 2,7 V
Fault confirmation time: 1 seconds.

Conditions of activation of the diagnostics: The following conditions have to be met:
- BSI triggered
- LIN networks re-awakened
Conditions for Fault to clear: Control copy active
Time of disappearance of the fault: 1 s
Downgrade Modes whilst Fault is active: None, but this may trigger the "SERVICE" warning lamp Warning message and / or an audible warning.
Symptoms: No supply of electrical components.
Suspect Areas:
  • Connectors
  • Electrical harness
  • Built-in systems interface
  • Supplies protection and management unit
So I would first check and test all the fuses in the supplies protection management unit as these power various equipment, but if the garage have tested it and are confident, then I can't do much more than provide the code description for this fault for you.
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Re: B1601 15 BSI Error code

Post by TiberGt »

This is the VIN: VF3**************[VIN obfuscated, can be read by forum staff]

I'll suggest this to the mechanic!
Thank you very much!