BMW Siemens MSV70 Engine ECU Repairs

Type: Siemens VDO Engine Management
Fits: BMW
Fuel: Petrol
Ref: AIC379325

Note: This ECU may also fit other models.

It does not matter which of the two numbers on a Siemens MSV70’s label you read first. Each Siemens reference in our table sits beside a BMW DME number, and every one of those pairings is confirmed by independent records, so either number will lead you to the right row and the other will confirm you have found it.

Below, we set out the BMWs the MSV70 is recorded in, how the label reads, why it should not be mistaken for an MSV80, the faults these units most often reach us with, and how the repair is handled.

Which BMWs use the Siemens MSV70?

The Siemens VDO MSV70 is an engine ECU, or DME in BMW’s own terms, used with the N52 six-cylinder petrol engine in 2.5 and 3.0 litre form. It is recorded in five model lines:

• 3 Series E90, E91, E92 and E93: 325i and 330i
• 5 Series E60 and E61: 523i, 525i and 530i
• 6 Series E63 and E64: 630i
• Z4 E85 and E86
• 1 Series: 130i

Five model lines, one engine family, one type of ECU. That is as far as the car can take you. The listings behind our eleven references mix these models freely, so none of the eleven can be pinned to a particular model, body style or engine size.

Knowing that your BMW has the N52 engine tells you to look for an MSV70. It does not tell you which one; the label does.

Two numbers on the label, and either one finds the row

An MSV70 label carries two part numbers: a Siemens reference beginning 5WK, and BMW’s own number, written as DME followed by seven digits in three groups. In our table, for instance, 5WK90077 is paired with DME 7 553 166.

All eleven pairings in the table are confirmed, so the lookup works from either side. Start with whichever number is clearer on your case, find it in its column, and compare the number printed next to it with the other one on your label. If the two agree, that row is your unit.

If they do not agree, or your number is not in the table at all, quote the label exactly as printed and our engineers will work from that rather than from a best guess.

One reference needs care when you copy it. 5WK900979 has six digits after the 5WK, where the other ten have five. That is how it is printed on the unit and how the trade lists it, not a mistake, so write it out in full rather than trimming it to match its neighbours.

MSV70 or MSV80: check the numbers, not the name

The MSV80 is a different, later unit with its own part numbers. On a worn label, or in a listing written in a hurry, the two names are only one character apart and easy to swap.

That is why the numbers matter more than the name. If your Siemens reference and DME number are both absent from our MSV70 table, do not assume the unit belongs on this page; send us the label details and we will confirm what it is before anything is posted.

The faults MSV70s most often arrive with

The second table on this page is our own. It lists the faults MSV70 units are most often sent to us with: no spark, no communication, a non-starter and water ingress.

It is a record of what brings these units in, not a diagnosis of yours. If one of the four matches what the car is doing, mention it in your enquiry; testing then establishes what has actually failed, and you hear the result before any repair is agreed.

Testing, repair and the 24-month warranty

We work by post, taking in units from anywhere in the UK, and every MSV70 is repaired in-house by our own engineers in our own UK workshop, on our own equipment. Nothing is sent out to another company.

Each unit is logged on arrival, inspected by eye and tested electrically before fault-specific diagnostics begin. We then contact you with what we found and a quote for the repair, and nothing chargeable is done until you authorise it.

The repair itself is made at component level, under a microscope with temperature-controlled rework equipment, so the part that failed is dealt with rather than the whole unit being swapped. It is not complete until the unit passes final testing, and the specific repair carried out is covered by our 24-month warranty.

Sending in your Siemens MSV70

To begin, enter whichever number you can read on the Repair Form, along with the other if it is legible, the BMW the unit came from and any of the four faults it showed. Our engineers will confirm from those details that it is an MSV70 we cover.

For any other BMW engine ECU, see BMW units outside the N52 family. If the car is not a BMW at all, start from a different manufacturer.

The eleven Siemens references and the BMW DME number confirmed for each are listed below, with the common faults table after them.

Common part numbers associated with this type of unit

Common faults associated with this type of unit