U0073 — Control module communication bus A off
Universal diagnostic code. Below: what it means, common causes, symptoms, and the exact bench-programming fix path.
Common causes
- •CAN-H or CAN-L short to ground
- •Missing 120-ohm terminator
- •Failed module shorting the bus
Symptoms you'll see
- •Multiple module no-comm
- •Crank-no-start in many cases
- •Cluster errors
The fix path
Diagnose wiring + terminators first. If a specific module is identified as the bus-killer, bench-repair or replace that module.
AML services that fix this
Mail in the affected module and we work it on the bench. Most jobs ship back the next business day; ABS repairs take about a week on the bench (2–3 business days with rush repair). Flat pricing, flat-rate return shipping at checkout.
Mercedes EIS Cloning (Pre-2014)
$250Failed Mercedes EIS leaving you with a car that won't start? We clone it to a replacement EIS — your existing keys keep working, no re-keying the car.
Service detailsABS Module Repair
$499ABS warning, brake lights, or traction control faults? Ship your ABS module for repair + reprogram.
Service detailsJaguar / Land Rover KVM/RFA Virginize
$300Used KVM or RFA module that your Range Rover or Jaguar refuses to accept? Ship it in — we wipe it back to virgin so it pairs to your VIN.
Service detailsRelated diagnostic codes
Not sure which service applies?
Text us your year/make/model + which scanner caught the code — we'll tell you exactly which module to ship and which service to pick.