NOx Sensor 857646901

BG 201036 (OE A0101539628): function on the vehicle

NOx Sensor 857646901 is supplied by BEST GROWTH under part number 201036, cross-referenced to OE A0101539628, as a direct-fit aftermarket nox sensors. In service it acts as the closed-loop feedback element of the SCR circuit: it tells the controller how much NOx is still leaving the catalyst, so dosing is trimmed up or down instead of running to a fixed map.

BG 201036 is built to the position defined by its OE application on a 12V electrical system in truck service on the platform from BMW. Position, calibration and connector layout are part of the specification, so a part that physically fits is not automatically the correct part.

Cable length and connector keying are part of the specification. A cell with correct electrical output but the wrong lead length will not route to the OE bracket.

Fitment for BMW and OE cross reference

BG 201036 replaces 4 OE references: A0101539628, 857646901, 5WK9 6659C and 5WK9 6697B, covering cross applications. Always confirm the number printed on the removed part, including any supersession issued by the vehicle manufacturer.

Recorded vehicle coverage for 201036 includes BMW, typically on BMW 3 Series F30 / F31 BMW X5 E70 / F15 BMW X6 E71 / F16. Coverage lists are a starting point for identification, not a substitute for checking the OE number on the vehicle.

Where several OE numbers appear against one BG reference, they are supersessions or regional variants of the same specification. Ordering by A0101539628 and quoting the number on your part lets our technical team confirm the variant before despatch.

Symptoms that lead to replacing A0101539628

These complaints bring a vehicle in with the BMW nox sensors under suspicion. None of them prove BG 201036 has failed on its own, which is why the checks below matter before a replacement is ordered.

• no communication with the sensor control module after a cold start
• sensor value frozen at a fixed number once the exhaust warms up
• dosing shut-down after a few minutes of steady-state running
• upstream and downstream values reading almost identically under load
• intermittent fault that clears after the engine cools and returns when hot

Checks before fitting BG 201036

Aftertreatment faults are usually system faults. Working through these checks prevents a repeat failure after the new nox sensors is fitted.

• Check for a pending software or parameter update for the sensor control module on that platform.
• After fitting, run the manufacturer's adaptation or relearn so stored efficiency counters reset.
• Compare upstream and downstream NOx readings warmed and under load — idle values prove nothing.
• Confirm supply voltage, ground quality and bus termination before condemning the sensor module.
• Inspect the harness for heat damage and the connector for moisture and green corrosion.

Quality, packaging and ordering 201036

BG 201036 is manufactured and tested to aftermarket replacement standards, with electrical, leakage and functional testing carried out before packing on the 12V specification. Bulk and retail packaging, private-label cartons and customer-specific labelling are available for distributors and workshop groups.

Send OE A0101539628 or the number printed on your part, the engine code and the vehicle identification number with your enquiry, and our technical team will confirm the correct reference, current stock position and lead time before you commit to an order.

Frequently asked questions

Does BG 201036 replace OE A0101539628?

Yes. BG 201036 is listed against A0101539628, 857646901, 5WK9 6659C and 5WK9 6697B. Confirm the number printed on the removed part and any manufacturer supersession before ordering.

Which vehicles does BG 201036 fit?

Recorded coverage includes BMW. It is supplied as a direct-fit aftermarket nox sensors on 12V systems. Adaptation, reset or relearn procedures required by the vehicle manufacturer still apply after installation.

Does this fault code always mean the nox sensors has failed?

No. Exhaust leaks, wiring and connector damage, reductant quality, dosing performance and upstream engine faults can all produce the same codes. Validate those inputs before replacing BG 201036.