In the 2009 Scion tC, the powertrain control module and engine control module manage engine timing, fuel delivery, and transmission coordination. A failure typically disrupts communication, triggers diagnostic codes, and may cause loss of power or no‑start conditions.
When a 2009 Scion tC begins to exhibit intermittent power loss, erratic idle, or diagnostic trouble codes, the powertrain and engine control modules are common culprits. Understanding how these computers function, what labor is involved in swapping them, and the post‑install procedures can help you decide between a repair or a refurbished replacement. This guide walks you through the basics so you can make an informed choice for your vehicle.
The powertrain control module in a 2009 Scion tC governs the interaction between the engine and transmission, while the engine control module fine‑tunes fuel injection and ignition timing. Both modules are essential for reliable performance and emissions compliance. A malfunction can trigger loss of driveability, cause the check engine light to illuminate, and store codes such as P0606 or P0607. Proper operation ensures the vehicle runs smoothly, and replacement units must match the vehicle’s specifications. 2009 Scion tC replacement modules are designed to fit the existing harnesses and retain original calibrations.
Both the PCM and ECM reside in the engine compartment, mounted near the firewall and secured with bolts. Removing a unit typically involves disconnecting the main power connector, unfastening the mounting bolts, and extracting the module. Installation reverses the steps, with the book time listed as 0.4 hours for each module. After the new unit is seated, the connectors are reattached and the bolts torqued to factory specifications if provided.
| Operation | Configuration | Book Time |
|---|---|---|
| Powertrain Control Module R&R | All configurations | 0.4 hr |
| Powertrain Control Module Relearn | All configurations | 0.5 hr |
| Engine Control Module Relearn | All configurations | 0.5 hr |
| Engine Control Module R&R | All configurations | 0.4 hr |
After installing a new module, the factory procedure requires a specific relearn sequence: the PCM relearn takes 0.5 hours and the ECM relearn also requires 0.5 hours. Flagship One units arrive pre‑programmed to the vehicle’s VIN, so those steps are already completed. a VIN-programmed replacement unit eliminates the need for field flashing and reduces the overall shop time.
Typical signs of a failing PCM or ECM in a 2009 Scion tC include a no‑start condition, rough idle, unexpected stalling, and loss of transmission shift quality. Diagnostic scanners often report communication failures, and you may see codes such as powertrain control stored in the system. Addressing these symptoms promptly can prevent further drivetrain issues.
The following internal trouble codes are commonly recorded when the powertrain or engine control modules malfunction in this vehicle:
| Code | Meaning | Full Guide |
|---|---|---|
| P0606 | Module processor failure | Full P0606 guide → |
| P0607 | Module performance fault | Full P0607 guide → |
Service bulletin S‑SB‑0003‑10, dated April 2011, applies to the 2009 Scion tC and outlines the Techstream ECU flash reprogramming procedure required for certain updates.
| Bulletin | Subject | What It Addresses |
|---|---|---|
| — | 04-11 Applicable Scion Vehicles: Techstream ECU Flash Reprogramming Procedure | — |
Yes, a malfunctioning PCM can interrupt fuel and spark control, leading to stalling under load. Replacing the module and completing the relearn steps usually resolves the issue.
The replacement typically requires basic hand tools to remove mounting bolts and disconnect the harness. No specialized programming equipment is needed if the unit is VIN‑programmed.
Factory guidelines specify a 0.5‑hour relearn to ensure the new ECM calibrates to the engine. Using a pre‑programmed unit can bypass this step.
When your 2009 Scion tC needs a control module, you can either have the original unit repaired or install a refurbished replacement. Both options restore functionality, but a refurbished unit often arrives with the necessary VIN programming, reducing shop time and simplifying the process.

Flagship One stocks a refurbished, VIN-programmed PCM for the 2009 Scion tC with a lifetime warranty, free shipping and no core charge. The full Scion tC module lineup covers other engine configurations as well.
The powertrain and engine control modules are vital to your 2009 Scion tC’s performance. Whether you choose repair or a refurbished replacement, ensuring proper installation and programming will keep the vehicle running reliably. Consider your options and act promptly to avoid further issues.