Network
generic / SAE
U012D
Lost Communication With Generator A Control Module
ECU lost CAN communication with generator (alternator) A control module. 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 / 2D
Possible causes
- Module unpowered 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: shop recommended
- Estimated cost: 100–1500 €
- Estimated time: 1–5 h
- Component: generator a module
- Component: can bus
- MIL / check engine light
- drive cycle required
Sources
References
sae:J2012