Network
generic / SAE
U0070
Communication Bus "B" Performance
The secondary communication bus (Bus B, often a chassis or comfort sub-bus) shows reduced performance — high error rate, intermittent dropouts, or framing errors. Bus is still alive but unreliable.
SystemNetwork
Typegeneric / SAE
GroupU0
Range / number– / 70
Possible causes
- Marginal wiring or corroded connector high
- EMI interference (aftermarket equipment) medium
- Gateway module routing CAN messages incorrectly 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: hard
- DIY: shop recommended
- Estimated cost: 80–1200 €
- Estimated time: 1–5 h
- Component: can bus wiring
- Component: can terminating resistor
- MIL / check engine light
Sources
References
sae:J2012