Lost Communication With Special Purpose Vehicle Control Module A
The vehicle bus reports loss of communication with special-purpose vehicle (SPV) control module A. Upfit functions like emergency lighting, sirens, fleet relays or PTO/auxiliary systems controlled by this node stop responding.
Affected components
- Special purpose vehicle module a
- Vehicle bus wiring
Common causes
- High likelihood: Bus wiring open or shorted
- Medium likelihood: Module without power or ground
- Medium likelihood: Module failed
Possible 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
Diagnostic notes
- A drive cycle may be required after repair
Related codes
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.