VW / Audi / Seat / Skoda (VAG) Bosch EDC15P+ Engine ECU Repairs

Type: Bosch
Fits: VAG – Audi / Seat / Skoda / Volkswagen (VW)
Fuel: Diesel
Ref: ECUT330225

Note: This ECU may also fit other models.

Two things can happen to a failed EDC15P+. Either a unit out of another car takes its place, or the one that came out of yours is repaired and goes back in. They are not the same job, and what separates them has less to do with the repair than with which ECU the car is left running afterwards. This is a diesel engine ECU, and testing and rebuilding these units in full is our own work.

A unit that comes from another car arrives as that car’s ECU, and something has to close that gap before it will run yours. It is adapted and coded to the vehicle. Or it is supplied with the immobiliser function bypassed, so that the car stops asking the question. Or the data held on your original unit is transferred across onto it. Three separate routes, and every one of them is work on the unit’s data rather than on the fault in the hardware.

Repairing the unit you already have never raises that question. The board is the one your car was built around, and it keeps the coding and the immobiliser pairing it already holds, because nothing about its identity changes while it is with us. It goes back in as itself. There is no adaptation to arrange afterwards, and no decision to make about the immobiliser, because the unit going back is the one the car already knows.

Bypassing an immobiliser, transferring data, cloning, coding and tuning are none of them work we take on. What we do is test the engine ECU and repair what has failed on the board.

What does fail inside these units is documented consistently. Independent repairers list the same short set against them: an internal control-module fault reported against the unit’s own memory, an engine that will not run at all, a unit that has stopped communicating over CAN, and no control of the fuel-pump relay. Two more are physical rather than electronic: solder joints that have gone dry, and water that has found its way inside. Any of those is a repair; none of them is a reason to change the ECU’s identity.

That set is worth reading against your own car before anything is posted. An engine that turns over and will not fire, a diagnostic tool that cannot reach the engine controller at all, or a fuel-pump relay the ECU is no longer driving: those are the symptoms that point at the unit itself.

The list below is not confined to one engine. Most of it belongs to the four-cylinder 1.9 TDI cars — Golf Mk4, Bora, Beetle, Passat, Octavia and the Sharan among them, on engine codes including ATD and ASZ — but the smaller three-cylinder 1.4 TDI cars are on it too, the Polo and the Audi A2 included.

That list runs to ninety-nine rows. Read the numbers off your own unit and find the row they match. If they are not on it, the EDC15P units we take in are listed separately.

The route a unit takes through the workshop does not vary. It is recorded against a job the day it arrives, examined for physical damage, and put on electrical test. You are told what that test found and what the repair would involve, and the decision to go ahead is yours before any chargeable work starts. The fault is then put right on the board it sits on: the failed component identified at the microscope and changed with temperature-controlled equipment, by the same engineers who tested the unit, with no part of the job sent out to anybody. Testing is also the last thing that happens to it, and a unit that does not pass does not go back. The repair itself is covered for 24 months.

If the car is a Volkswagen and the ECU in it turns out to be something else entirely, every other Volkswagen engine ECU we handle is grouped in one place. Units reach us by post and go back the same way, from anywhere in the UK.

If the unit in front of you came out of your own car, it is already matched to it, and the work left is to find out what has failed on the board. Send us the numbers from it, with a line on what the engine is doing, through the Repair Form on our contact page.

Common part numbers associated with this type of unit