Network
generic / SAE
U01B1
Lost Communication With Particulate Matter Sensor B
ECU lost communication with particulate matter sensor B (downstream of DPF, used for DPF integrity monitoring). A communication loss with this module breaks any function relying on its data — diagnostic tools may show 'no response' and dependent modules can fall into limp mode.
SystemNetwork
Typegeneric / SAE
GroupU0
Range / number1 / B1
Possible causes
- Sensor unpowered or wiring broken high
- Gateway module routing CAN messages incorrectly low
- CAN terminating resistor (120 Ω) drifted out of spec low
Symptoms
- Multiple warning lights may illuminate
- Affected modules may go into limp mode or shut down
- Specific functions inoperative depending on module
- Diagnostic tools may show communication faults
Inspection / repair
- Difficulty: medium
- DIY: possible
- Estimated cost: 100–800 €
- Estimated time: 0.5–3 h
- Component: pm sensor b
- Component: can bus
- MIL / check engine light
- emissions-relevant
- drive cycle required
Sources
References
sae:J2012