VE.Bus Error 11, Step 0

Been chasing a gremlin in my shepherd's hut setup for the past fortnight and wondering if anyone else has hit the same wall.

Running a Multiplus II 48/3000 with a 16s LiFePO4 pack and Fogstar Drift cells, managed through a JK BMS talking to Cerbo GX via CAN. Most of the time it's rock solid — genuinely one of the more satisfying builds I've done.

But occasionally, usually first thing in the morning when the BMS is waking up and the Multiplus is trying to initialise, I'm getting a VE.Bus Error 11 flagged in Venus OS. Specifically it seems to be hanging at Step 0 of the pre-charge sequence, then recovering on its own after a minute or two. No actual power loss, just the error sitting there in the notification log like a bad omen.

My suspicion is the BMS is a fraction slow to assert the DVCC charge voltage before the Multiplus decides something is wrong — but that's mostly guesswork at this point.

A few things I've already tried:

• Lowered the Battery monitor scan delay in VEConfigure
• Checked all the CAN termination resistors (both ends, 120Ω confirmed)
• Verified firmware is current on everything

It always clears itself, which makes me think it's a timing or handshake issue rather than anything fundamentally broken. But "it sorts itself out" isn't really good enough when you're relying on this for your only power source.

Has anyone got to the bottom of one of these? Particularly interested if you've solved it on a JK/Cerbo combination.

@MuddyNomad VE.Bus Error 11 Step 0 is almost always a communication issue between the Multiplus and the BMS rather than a hardware fault — don't let it send you chasing your wiring unnecessarily.

Few things worth checking:

• VE.Bus BMS assistant — is it loaded in the Multiplus? Without it, the Fogstar Dri's charge/load disconnect signals get ignored
• Check your two-wire BMS cable connections at the Multiplus AUX port, even a slightly loose pin causes this intermittently
• What firmware is your Multiplus on? There were known issues pre-490 with certain BMS handshakes

Had something similar on my garden office build. Turned out the assistant configuration was wiped after a firmware update — took me ages to spot it.

Worth grabbing VictronConnect and checking the assistant list directly on the unit before assuming anything's physically wrong.

@MuddyNomad had almost identical grief on my narrowboat last spring — same error, same head-scratching.

What finally cracked it for me was the VE.Bus cable itself. I'd assumed Victron's own cabling was bulletproof, but one end had a slightly loose crimp that only showed up under load when everything was warm. Swapped it out and the error vanished overnight.

Worth also checking whether your Multiplus firmware is current — there was a patch a while back specifically addressing handshake timing with third-party BMS units. VictronConnect makes it painless to check.

If you're running the Driftwood BMS via CAN rather than VE.Bus direct, double-check your termination resistors at both ends of the bus. Missing one will cause exactly this kind of intermittent step-zero failure rather than a clean hard fault.

@MuddyNomad VE.Bus Error 11 Step 0 specifically means the Multiplus couldn't complete its pre-charge sequence — it's not just comms grief, it's the inverter refusing to energise because it detected something wrong at Step 0 of the startup handshake.

Classic culprits on 16s packs:

• Cell imbalance >100mV at rest triggering the BMS to assert a charge-inhibit during pre-charge
• Dodgy RJ45 on the VE.Bus cable (I've replaced three of these on my own rig — crimp quality is shockingly variable)
• BMS DVCC settings in VenusOS fighting the Multiplus charge algorithm

Check your VictronConnect VE.Bus diagnostics tab — it'll timestamp exactly when Step 0 failed relative to BMS allow-to-charge signal.

@JackeryNerd is right about comms, but the sequence matters enormously here — it's not just whether they're talking, it's when.

@MuddyNomad what BMS are you actually using? You said "Fogstar Dri" and then the post got cut off. Makes a big difference.

If it's the Drift BMS, check whether you've got the DVCC settings configured properly in VenusOS — wrong SVS/STS settings will cause exactly this. Also make sure your VE.Bus cable isn't daisy-chained through anything sketchy.

Had similar grief in my shepherd's hut before I sorted the charge current limits being sent from the BMS. Multiplus was getting confused by conflicting signals.

Share your VEConfigure screenshots and the BMS comms setup. Guessing in the dark otherwise.

Great thread, @MuddyNomad — I've dealt with this exact scenario a couple of times now.

One thing nobody's mentioned yet: check your pre-charge resistor if you're using one externally, but more importantly, look at your DC cable run between the BMS and the Multiplus. A dodgy connection or undersized cable can cause enough of a voltage drop during pre-charge that the Multiplus simply gives up.

Also worth checking VictronConnect — the detailed error history sometimes shows whether Step 0 is failing immediately or after a few seconds, which tells you a lot about whether it's a communication issue versus an actual pre-charge hardware problem.

@OldSailor is right about what the error means — so the question really becomes why pre-charge is failing. Get us the full BMS model and I reckon we can narrow it down sharpish.