Alto-Shaam Combi Oven Error Code E45: B10 Probe Shorted
E45 B10 Fault means the multipoint core probe B10 is shorted to ground. Press the Start icon to acknowledge it, unplug and inspect the probe, and call if the message returns.
Low: only core-temperature probing is affected and time-based cooking continues.
- Code
- E45
- Maker
- Alto-Shaam
- Equipment
- Combi ovens
- Applies to
- Combitherm CT PROformance (CTP) and CT Classic (CTC)
What does Alto-Shaam error code E45 mean?
The multipoint core probe B10 is the probe you place in food so a program can track the core temperature. Its circuit should read as a temperature, not as a direct connection to ground. If the control sees a short, it posts E45 B10 Fault for the probe as a whole. The only cause the manual gives is a miswired or malfunctioning probe. This is a different message from E22, which reports B10 as defective or disconnected, and from E46 to E48, which name a short at an individual sensing point. A short at the plug or in the cable can show up on the whole probe, since the leads are shared. Start acknowledges the message and the oven tries to resume. The shorted probe keeps failing until the damaged part is replaced, but time-based cooking does not use it.
Affected models and control systems
CTP and CTC combi ovens, 6-10 to 20-20, electric and gas, fitted with the multipoint core probe, B10.
Code numbers and their meaning can change between control generations. We match the full model and control before acting on a code.
What you may notice
- E45 B10 Fault on the display
- Core-temperature cooking not available
- Probe plugged in with no temperature shown
Possible causes
Listed in Alto-Shaam's documentation
- Probe B10 miswired or failed
Other likely causes — what usually sits behind error code E45 on this control. A technician confirms which one it is before any part is replaced.
- Water inside the probe plug after being washed with the handle submerged
- A cable cut through its insulation at the door seal
Safe checks before calling for service
- Press the Start icon once to acknowledge E45.
- Remove the probe, dry the plug fully, and check the cable for cuts.
- Plug the probe back in and try again.
- If E45 returns, cook by time and tell the technician whether the probe was washed.
How a technician diagnoses error code E45
- Read the code and check history for E22 and E46 to E48.
- Inspect the probe cable and plug and dry them out.
- Measure each probe lead to ground with the probe disconnected.
- Check the oven receptacle wiring for a short.
- Replace B10 if the probe itself is shorted.
- The tests require a meter and the probe fully disconnected.
- The receptacle wiring leads to a live control board.
- Food-safety temperature decisions depend on this probe.
How error code E45 differs from similar codes
E22 is B10 defective or disconnected, E26 to E29 are open sensing points, E45 is the probe shorted, and E46 to E48 are individual points shorted.
Technical reference
- Maker documentation
- Alto-Shaam owner support
- Edition
- MN-35949 Rev 08 03/22
- Models / control
- Combitherm CT PROformance (CTP) and CT Classic (CTC)
- Section
- Error Codes, pp. 25-31
- Checked
- October 2026
We use the maker's document to read the code and do not reproduce it. Always confirm the complete model and control before applying these steps.
Related Alto-Shaam combi oven error codes
Can I wash the probe?
Water in the plug is a plausible path for a short, so dry it and follow the manufacturer's care instructions.
Is E45 the same as E46?
No. E46 names point 1 of B10; E45 names the probe as a whole.
Do I need a new probe?
Often yes, if drying does not clear the message.
Need help with Alto-Shaam error code E45?
A technician confirms the cause on site and gives you the price in writing before any work starts.