2009 ML 320 Bluetec persistent fault code 14A600, lack of power, anybody encounter this problem? fault code 14A600 - positive control deviation of exhaust gas recirculation control is too high. The engine has excellent idling, start quickly and no smoke at tail pipe but unable to rev over 3000 rpm. No other fault code appearing. I already replaced the two orange seal at turbo inlet and PCV inlet on the clean air Y-pipe then smoke test the entire inlet from engine air filter to the intercooler outlet but no leak was detected in and outlet pipe of the turbo. Removed and cleaned EGR valve not much soot found, inspected the internal corrugated EGR pipe, no deformation or obstructions found, remove the EGR pipe from EGR cooler outlet and found it was clogged, removed the harden soot from the pipe, blow compressed air to the EGR cooler and pipe. I thought this was the only problem but when I test drive the SUV the fault code had come back again. I Checked the continuity of all the wires from the harness, those wires coming from MAF sensor, throttle intake temperature sensor, EGR inlet temp sensor and oil temp sensor all signal wires have continuities. I also I checked the opening and closing of the EGR valve by supplying 12 volts power to the EGR terminals and it opens and closes smoothly. I believed no issue with wiring harness. I appreciate your comments, thank you.

Based on the wiring diagram provided by Maj. Dundee I was able to back probe the CDI/ECU terminal # 71 and took continuity test from #71 to EGR terminal 1, the wire is good. I also install a brand new Exhaust Back Pressure sensor but still the same fault code 14A600 keep coming back. The sad concern now is the EGR valve I might end up replacing it and it is too expensive. Any experience you can share before I replace this expensive part or probably just delete this EGR valve.

Bonjour, je rencontre le même problème.
Tourne bien au ralenti, mais des que je monte et maintient un régime plus élevé le moteur broute.
La voiture manque de puissance.
La vanne egr a été remplacée.
Capteur de pression du turbo a été remplacé.
Capteur de pression des gaz d échappement a été remplacé.
Rien ne fonctionne.
J'espère que quelqu'un pourra m'aider.
Merci

Bonjour Kain99584, Avez-vous vérifié tous les fils / connecteurs de faisceau de câbles de la vanne EGR à l'unité CDI et également à l'actionneur de suralimentation turbo et au moteur du volet de turbulence?

Avez-vous vérifié toute fuite d'air sur l'admission entre les filtres à air et l'entrée et la sortie du turbo vers la sortie du refroidisseur intermédiaire vers la boîte de mélange du corps de papillon. Avez-vous également nettoyé le tuyau d'admission EGR après le refroidisseur EGR?

Après avoir remplacé chaque composant, vous devez supprimer le code. As tu?

Maj Dundee, I ended up replacing the EGR valve recently but still did not fixed the fault code 14A600 - positive control deviation of exhaust gas recirculation control is too high. In the morning when driving out after erasing fault code, the check engine light will be illuminated only after 30-40 km or 15-20 min drive or when the engine is warm. I can see that the EGR valve is opening and closing initially 15%, 30%, & 45% from my scan tool while leaving my garage and when cruising the freeway but after 15-20 min drive the check engine light will come in again. As you can see from my previous threads. I have lots of test and parts replacement been done already including a thorough air leak/smoke test of the intake; replacing the 2 orange seals on turbo inlet and PCV inlet to MAP sensor, new air filters, new exhaust back pressure sensor, tested all the wirings and connectors from ECU to EGR valve and to turbo actuator and swirl flap motor, exhaust temperature sensor all are good. I also replaced all the seals, o-rings and gaskets of the throttle body and intake mixing box including cleaning of the EGR admission tube. I would appreciate any suggestions. Thank you.

This code 14A600 refers to part# Y27/9. Did any of you replace it?

Yes, it was replaced with a brand new very expensive parts.

Things were very difficult to upload these PDFs. You will need a M/B scanner.

Thank you Maj Dundee, will try this test again and will let you know.

Hi Maj. Dundee,
Here are the test results:

Engine RPM : 1400 rpm
Coolant temp : 195.8 deg F (check engine light come in at 195.8 deg F but at 176.8 deg F no check engine light so it only trigger when 190 deg F coolant temperature)
Commanded Throttle Actuator : 96%
Charge Pressure Positioner: 92 %
Exhaust Gas Recirculation Positioner : 0%
Sorry, my scan tool do not have M55 (inlet port shut off motor) live data so I cant get value. Please let me know further test.

I only provided information to check the problem and I do not own one of these money pit vehicles. I cannot help you any further.

Clean the pipe assembly downstream of the EGR valve, at the front of the engine bay.