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Discussion Starter · #1 ·
Hello everyone,

could anyone help deciding what next with my project. My AXE engine broke down. I couldn’t find same one so I bought AXD and fitted it. Engine starts and runs fine but automatic gearbox stopped working. Selector shows gear change but there is no drive. No error codes for gearbox. Communication with all systems apart from the engine. Ecu is from original engine so for AXE not AXD which is fitted in the van now.
Guys please help.
 

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The first thing is to find out why the engine ECU isn't communicating, I imagine the gearbox doesn't know what to do without the data from the engine.
What diagnostic kit are you using?
 

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Discussion Starter · #3 ·
The first thing is to find out why the engine ECU isn't communicating, I imagine the gearbox doesn't know what to do without the data from the engine.
What diagnostic kit are you using?
Thanks for reply. I’m using VCDS and Snap-on Zeus. ECU wasn’t reprogrammed or changed. I just changed the engine leaving original ecu on the van.
 

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That swap sounds like it should work in theory. The turbo and cam are different so you might expect some fault codes/EML light for low boost figures.

I agree with bluzie, you have to get to the bottom of the no communication fault with the engine first. I'd check all fuses both in the cab and especially under the bonnet first. Then look at the ECU for missing earths, loose multiplugs or damage from the swap.
 

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Thinking about your fault a bit more it seems odd that no other controller is complaining about not being able to talk to the engine (which they all do via the CAN system even on your old van) so I think the communication between the various controllers (air bag, ABS, Conv, Cent Elec etc) must be good otherwise you would certainly have fault codes. This is assuming that you have checked all controllers of course.

Usually no communication with the ECU goes with poor running or a non-start. So I'd say if all fuses, earths and ECU connections are ok forget the engine ECU just for now and have a look at the live data in the transmission controller (02) with VCDS in case of some physical problem like a damaged torque converter. If you have a genuine registered VCDS cable and you go to the transmission controller (02) then with the engine running go to 'Measuring Blocks' scroll up through the groups then hover over each block of digits. A bubble should pop up with the range of expected values for each item. (Torque converter speed, engine speed, fluid temp, pressures etc)

If the top left of the VCDS screen shows a lbl file you will get more detailed info. No silver bullet but at least it is a start and you should be able to spot something big like the torque converter not working. Did you take the torque converter off with the engine and lose fluid? You did fill it back up didn't you... :D :unsure:
 

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I did the reverse switch. It should work fine. I don't even think the cam is different, but I might be wrong. Did you swap the turbo? If you swapped the turbo, you have fitted an AXE and you won't need to remap it. If you retained the AXD turbo, it will probably throw an overboost code and go into limp mode, but you should be able to drive it to get it remapped with a light foot. It was fine with an AXD to AXE swap, but did throw an under-boost code a few times (the boost comes in later than my ECU was expecting with the bigger turbo). Might be worth getting someone to work the gearstick and check the linkage on the gearbox, just to make sure it is going into drive. Did you drain the autobox when you removed it?
 
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