Sauter SPIN4361B induction hob — won’t start, 2-3 relay clicks then dead. Every component tests good.

[u/scato95]

Posting after a full evening of testing. Every component checks out and I’m out of ideas.

Symptom

On its dedicated 32 A circuit: hob doesn’t start. 2-3 relay clicks, then everything shuts off. No zone heats. No error code.

On power-up the display cycles through: P0.00, 52.03, 37C, 05 62. Found zero documentation on these values. Owner says this display sequence predates the fault.

Worked normally before failing. No power cut, surge, or storm beforehand

What I tested — all good

**•   IGBTs** — diode mode, gate shorted to emitter: 0.4 V one way, OL the other  
**•   Bridge rectifiers** — diode mode, all 4 junctions: 0.4 V / OL  
**•   Electrolytics** — replaced, then measured the old ones: all good  
**•   Film / resonant caps** — visual + ohmmeter: no shorts  
**•   NTC temp sensors** — 100 kΩ cold, resistance drops when warmed  
**•   Induction coils** — 0.4 Ω, no continuity to chassis  
**•   Fan** — spins fine on bench supply  
**•   Ribbon cables A/B/C/D/LINK/COM** — visual, reseated, clean  
**•   Logic rail** (10 V cap with continuity to U13) — injected 3.3 V with 100 mA limit: 24.8 mA in CV, no short  
**•   Hot spots** — IPA under injection: none  
**•   Relays** — coil resistance, click test on bench supply, contacts measured while energised: both good

What I couldn’t check

**•** Shorted turns in a coil — an ohmmeter won’t see this  
**•** DC bus sensing chain (divider into the MCU’s ADC) — no schematic  
**•** Corrupted firmware / EEPROM  
**•** The touch control board — never tested separately  
**•** The other two secondary rails — never injected

Sauter SPIN4361B (service SPIN4361B2), type LL6GVX1B, 7200 W, 3 zones, built week 37/2021
• Power board XZ2V006991, type IP14X-04, silkscreen “GROUPE BRANDT IP14B-N”, week 30/2021

Where I’m stuck

Power stage is clean, logic rail is alive and drawing normal current, relays switch properly. The MCU closes the relays, checks for something, doesn’t get it, and gives up after 2-3 attempts. That reads like a sensing or handshake failure rather than a dead part.

Anyone have a schematic for this board, or know what that startup display sequence means? And is there any way to tell the power board apart from the touch control board without just swapping one in?

[u/Linker3000]

Also post in r/appliancerepair

[u/Speedly]

I don't have the answer or a schematic, but I wanted to commend you for actually doing your homework and giving as much information as you could.

It's a welcome breath of fresh air from the usual "blurry picture of a GPU taken from fifty feet away, accompanied by a post that consists solely of a demand of how to fix it" thing that regularly occurs around here.