2A70

What Code 2A70 Means

Code 2A70 (CDKDIVVT, Fehler Stromplausibilisierung) is stored in the engine control module (DME) and belongs to the Valvetronic system. The fault indicates a current mismatch in the Valvetronic motor control circuit — the DME sees current outside the expected range for a given position. Valvetronic provides continuously variable valve lift, and its correct operation is critical for cylinder filling across all operating conditions.

The electrical circuit includes the Valvetronic motor, the intermediate connector, and the wiring to the DME. When current plausibility is violated, the DME can't reliably control eccentric shaft position, so actual and commanded valve lift diverge. That affects mixture formation and engine operation, especially on cold start and during sudden throttle opening.

Symptoms

• Engine start: hard starting, especially cold, with rough running in the first seconds after startup.
• Performance: power loss at low rpm, no response to the throttle.
• Operating modes: transition to limp mode (noodloopmodus) when the current plausibility mismatch is detected.
• Engine operation: possible surging and instability at idle and under load.

Diagnosis and Repair

Step 1. Read the Fault Status

Run a proper diagnostic scan with ISTA or INPA to get the exact status of the engine fault and the Valvetronic sensor. Check for related codes and the conditions under which the fault set (temperature, rpm, Valvetronic position).

Step 2. Check the Electrical Circuit

Inspect the Valvetronic motor connector and wiring for corrosion, damage, and secure contact. Measure circuit resistance and compare it with reference values.

Step 3. Evaluate Temporary Measures

Unplugging the Valvetronic connector is a known temporary trick discussed on forums; it may help against surging for a while but is not a structural fix. Use it only to localize the fault, not as a repair method.

Step 4. Fix the Fault

Based on the diagnostic results, replace the Valvetronic motor or repair the wiring as needed. After the repair, run the Valvetronic adaptation and clear the fault memory with ISTA.