By Tom Beard, Dealer Development Manager, Frontier Power Products
Swapping electronic engine computers (ECU – Engine Controller Unit) has occurred often as a diagnostic procedure. We do it ourselves sometimes. What you may or may not be aware of is some consequences I’d like to explain.
Whenever a Tier-2 or Tier-3 John Deere engine ECU is swapped over to another engine, a situation occurs when a fresh or updated payload is attempted to be uploaded. This situation is referred to as a “serial number mismatch”. If the 2 engines involved are identical in power rating and trim settings, you may not notice anything different and the engine will run and likely run OK. Beware, however, if swapping ECUs to similar engines (ie. same model & displacement but not the same payload or software parameters); if the power rating or throttle settings are different, you will run into problems, possibly affecting starting and performance. This will also cause the engine to be out of emissions compliance. Engine ECUs are serialized like the engine, and both are “associated” to each other within the payload. Most people are not aware of this.
What happens is this; installing a payload to an ECU not associated to a specific engine serial number gets an error of “10-573-134: ECU serial number does not match the expected serial number in the payload”, in other words “serial number mismatch”. This happens whenever a new blank “replacement” ECU is being programmed and the original ECU is not available, or when ECUs are swapped and left on the engine and a fresh payload is trying to be installed. In most cases, the upload process asks to be connected to the original ECU and therefore may avoid this error. This can also be avoided by ordering the new blank ECU pre-loaded with the current correct payload when placing the order. John Deere charges a fee for this additional to the price of the ECU. Typically this is not necessary for our dealers or OEMs with ServiceADVISOR™ programming tool and training.
Apparently this is all too common and can only be corrected with a DTAC case submitted to the factory engineers. Once they have tweaked the payload, then the new ECU serial number can then be associated to the applicable engines serial number when uploaded to the new ECU. Then a confirmation Return File must be sent back to John Deere to register the new ECU serial number to be accepted by the revised payload file.
What this also means, if not corrected, is you or another technician will receive this error when trying to install a fresh or updated payload at a later date, and be unable to complete the programming.
If you encounter this, contact your authorized John Deere Service Dealer or Frontier Power Products service department to submit a DTAC case to request this payload re-association. A ServiceADVISOR™ technician will then upload and correct this situation on site. Or, you may send in your ECU for this procedure and have it returned to you.