P0B35 code meaning
High Voltage Service Disconnect Circuit Low
Powertrain system Generic code P0Bxx codes Check engine light
What P0B35 means
P0B35 sets when the service disconnect detection signal stays below its lower limit. Where the loop is coded with a resistor in the plug, as in a Lear patent, a reading near zero typically points to a short to ground in the loop wiring; the exact meaning depends on how the manufacturer powers the input. Ford traced an intermittent short to ground in the low-voltage interlock wiring as the cause of its open-loop code P0B37 on the C-Max Energi, which shows how chafed harnesses act here. No manufacturer documents P0B35 publicly. CARB treats such signals as monitored hybrid inputs. High, open and performance faults are P0B36, P0B37 and P0B34. The contactors usually stay open.
P0B35 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor0.5 to 4 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P0B35
- No ready mode or stall with a stop-safely message
- MIL and high-voltage warning on
- Charging not possible
Common causes of P0B35
- Most likelyDetection loop wire chafed and shorted to ground
- PossibleMoisture or corrosion in the plug base bridging to ground
- Less likelyCoding element in the plug shorted
- Less likelyBattery controller input stage fault
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Hv service disconnect switchWiring harnessBms
What each part of P0B35 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| B | Area: hybrid propulsion. |
| 35 | The exact fault in that area. |
What to do next
- Note P0B35 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P0B35
What does P0B35 mean?
P0B35 means "High Voltage Service Disconnect Circuit Low". P0B35 sets when the service disconnect detection signal stays below its lower limit. It is a generic code, so it means the same on every make.
Is it safe to drive with P0B35?
Drive gently and only to a workshop. With P0B35 the car can go into limp mode (reduced power) to protect itself.
Will P0B35 fail an emissions test?
Yes, it can. P0B35 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P0B35 to fix?
Difficulty: workshop only. A typical repair takes 0.5 to 4 hours of work. This is a job for a workshop.
Will P0B35 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.