The generic P0773 description refers to an electrical fault associated with shift solenoid E. That letter is not a universal physical location or an interchangeable part number. Before ordering a solenoid pack or sending a controller away, establish what the code refers to on the fitted transmission.
A useful referral identifies the circuit
The report should state the exact gearbox, the diagnostic tool’s complete wording and the manufacturer information used to identify the circuit. Include the original code status and any related faults instead of selecting only the first code on the screen.
If several solenoid codes appear together, list them together in the enquiry. If only P0773 returns, record that too. Both observations are more useful than an assumption that the most expensive component is responsible. Preserve information about recent loom disturbance, fluid ingress reported by the garage, and replacement-controller history.
Explain what has already been done
“Wiring checked” should be accompanied by the relevant test result and conditions. “TCU changed” should include both old and replacement identification plus the programming history. This is especially helpful when the fault changed after an earlier repair attempt.
Ask AXION about TCU assessment before removing or posting components. Keep the original electronics and any diagnostic files. The enquiry can then distinguish a circuit investigation, a removed-unit assessment and a compatibility question, instead of treating all three as the same job.
Definition reference: HELLA generic powertrain code list. Use the vehicle manufacturer’s solenoid naming and test procedure.
Reviewed September 2026. Use the complete manufacturer-specific fault description and vehicle repair information.