Removing and installing turbocharger 1 control unit J724 - vehicles with engine codes CDUD, CPNB, CTBA and CTBC — AUDI
Removing and installing turbocharger 1 control unit J724 - vehicles with engine codes CDUD, CPNB, CTBA and CTBC on Audi: 43 steps, 3 torque figures.
Workshop procedure for AUDI — the exact step sequence and torque figures, straight from real workshop data.
🧭 Before you start
Fits: Audi Q5 (8R, 2008–2017)
- Renewed: bolts as follows
Don't miss
- In this example, software version Hella (item 1) is selected.
- If the display indicates "“[OK
- Do NOT unscrew any of the other bolts visible in the illustration.
- If the display indicates "“FAULT [OK
- If the display indicates "“FAULT”", the new turbocharger 1 control unit J724 must be renewed for a second time.
🔩 Torque settings
Values can differ between engine variants — check the code stamped on your block.
| Torque | Fastener / step |
|---|---|
| 10 Nm (7.4 lb-ft) | Tighten bolts (1, 2, 3) |
| 5 Nm (3.7 lb-ft) | Tighten bolts (1, 2, 3) |
| 8 Nm (5.9 lb-ft) | Fit bracketVAS 6395 /6 on centring hole of bracket for turbocharger 1 control unit J724… |
ℹ️ Always cross-check the exact figure against your vehicle's factory manual before final tightening — a wrong torque can damage the engine. These values are extracted from workshop data and may not cover every variant or revision.
📋 Procedure
- Remove engine cover panel .
- Lift off cover (1) by its handle.
- Release retainer (arrow A) and open cover (arrow B).
- Connect testerVAS 6395 A/1 with connection leadVAS 6395/2 to positive terminal (1) and negative terminal (2).
- Select software version with buttons ↑(item 5) and ↓(item 6).
- To confirm software version, press v button (item 4). [Note: In this example, software version Hella (item 1) is selected.] [Note: If the following appears on the display, an incorrect software version has been loaded:1. >TEST2. LEARNGerman market: If this is the case, download the correct software version from the "“Audi Partner Portal (under Service)”" in the section "“Workshop Equipment”".Rest of the world: If this is the case, download the correct software version from your Importer's information platform.]
- ⚠ Risk of damage to turbocharger 1 control unit J724.Before continuing, check whether the correct software version is loaded in the testerVAS 6395 /1. To do so, proceed as follows: — Unplug electrical connector for turbocharger 1 control unit J724.
- Connect connection leadVAS 6395/2 to turbocharger 1 control unit J724 and to testerVAS 6395 A/1.
- To continue, press v button (item 4). [Note: If the display indicates "“[OK]”", the adjustment range of the turbocharger 1 control unit J724 is OK.If the display shows "“FAULT [OK]”", tap gently several times on the housing of turbocharger 1 control unit J724 with the handle of a screwdriver and repeat the check by pressing v button (item 4).]
- Remove bolt (arrow). [Note: Do NOT unscrew any of the other bolts visible in the illustration.]
- Fit bracketVAS 6395 /6 on centring hole of bracket for turbocharger 1 control unit J724 and tighten bolt to 8 Nm. — 8 Nm (5.9 lb-ft)
- To continue, press v button (item 4).
- While the voltage value is being determined, keep tapping gently on the housing of turbocharger 1 control unit J724 until the display indicates the following:
- Note voltage value. [Note: If the display indicates "“FAULT [OK]”" or the voltage is less than 3.3 V or greater than 3.7 V, unplug testerVAS 6395 A/1 and repeat the complete procedure .The turbocharger must be renewed if no voltage value can be read out.]
- By pressing buttons ↑(item 5) and ↓(item 6), adjust turbocharger 1 control unit J724 so that coupling rod can be accessed easily for removal.
- Unclip circlips (arrows) and dispose of them, detach coupling rod.
- By pressing buttons ↑(item 5) and ↓(item 6), adjust turbocharger 1 control unit J724 so that bolts for J724 can be accessed easily.
- Disconnect connection leadVAS 6395/2 from turbocharger 1 control unit J724.
- ⚠ Power supply for testerVAS 6395 /1A must remain connected. — Remove bolts (1, 2, 3) and dispose of them. [Note: Do NOT unscrew any of the other bolts visible in the illustration.]
- Remove old turbocharger 1 control unit J724 and dispose of it.
- ⚠ Check that the three insulating washers are fitted between turbocharger 1 control unit J724 and the bracket. — Install new turbocharger 1 control unit J724 in reverse sequence of removal.
- Fit new bolts as follows:
- Initially hand-tighten bolts.
- Connect connection leadVAS 6395/2 to new turbocharger 1 control unit J724.
- To continue, press v button (item 4).
- Select menu item "“NEXT”" with ↓ button (item 6).
- To continue, press v button (item 4). [Note: If the display indicates "“FAULT”", the new turbocharger 1 control unit J724 must be renewed for a second time.]
- To continue, press v button (item 4).
- To continue, press v button (item 4).
- Insert coupling rod.
- Fit circlips (arrows).
- Press turbocharger 1 control unit J724 towards the rear without applying force (arrow) until lever (1) rests lightly on bracketVAS 6395 /6.
- Hold J724 in this position.
- Tighten bolts (1, 2, 3) to 5 Nm. — 5 Nm (3.7 lb-ft)
- To continue, press v button (item 4). [Note: If [OK] is indicated on display, terminate adjustment .If "“CHECK”" is indicated on display, proceed as follows.]
- Loosen bolts (1, 2, 3) until turbocharger 1 control unit J724 can just be moved by applying light force in the direction stated:
- Tighten bolts (1, 2, 3) to 5 Nm. — 5 Nm (3.7 lb-ft)
- To continue, press v button (item 4).
- Tighten bolts (1, 2, 3) to 10 Nm. — 10 Nm (7.4 lb-ft)
- To continue, press v button (item 4).
- Unbolt bracketVAS 6395 /6(arrow).
- To continue, press v button (item 4). [Note: If the display indicates "“FAULT”", the new turbocharger 1 control unit J724 must be renewed .]
- Unplug electrical connectors for testerVAS 6395 A/1.
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Who makes these pages, and how
TorqFix was built by a mechanic — after a 2,700 km drive with five roadside repairs that no diagnostic tool could explain.
The figures on this page come from manufacturer workshop documentation and are shown as they are. The page is assembled automatically from that data — it is not written by an AI. The AI works in the chat, where it answers for your specific car. It writes nothing here.
Variants of the same model differ. Cross-check torque against the factory manual for your engine before final tightening.
Seen a figure that does not match your manual? Write to us — we correct it and note when. support@torqfix.com
The story behind TorqFix →Workshop data on this page last updated 20 Sep 2026.