If vehicle coding information is not as specified:

Replace ECM.
NOTE:
- Vehicle information is "hard coded" into the ECM. Service coding of the ECM is not possible.
- Coding versions may be checked (only) using the VAG1551 or VAG1552 Scan Tool (ST).
- While checking coding versions, the 5-digit ECM code must always be displayed.
Connect VAG1551 or VAG1552 Scan Tool (ST) and press buttons -0- and -1- to insert "Engine Electronics" address word 01 (ignition switched on). See VAG1551 OR VAG1552 SCAN TOOL (ST), CONNECTING AND SELECTING "ENGINE ELECTRONICS" ADDRESS WORD 01 .

Indicated on display

Fig 1: V.A.G 1551 Scan Tool Display - Checking Engine Control Module (ECM) Coding (1 Of 3)

Press -Q- button to confirm input.

Indicated on display (ECM identification and coding)

Fig 2: V.A.G 1551 Scan Tool Display - Checking Engine Control Module (ECM) Coding (2 Of 3)

ECM CODING AND MODEL

Coding	Model
01273	A8 4.2 liter, engine code ABZ
01153	A8 3.7 liter, engine code AEW

Indicated on display

Fig 3: V.A.G 1551 Scan Tool Display - Checking Engine Control Module (ECM) Coding (3 Of 3)

Press buttons -0- and -6- to select "End Output" (scan tool function 06), and press -Q- button to confirm input.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Engine Control Module (ECM) coding, checking