Common Failures in Ford Delphi DCM 3.5 Engine Control Units
The Ford Delphi DCM 3.5 engine ECU, fitted to models built between 2009 and 2015, is a critical control unit responsible for managing engine performance, emissions, and communication with various sensors. While reliable in many respects, these ECUs are known to suffer from recurring faults that can leave vehicles difficult to diagnose or completely inoperative. Common issues include no communication with diagnostics, a constantly clicking vaporizer relay, and loss of the 5V reference supply to sensors, often accompanied by fault codes P06A6, P06A7, and P06A8.
Common Faults:
No communications
Vaporizer relay constantly clicking
Loss of 5V rail to sensors
Common Fault Codes:
P06A6 – Sensor Reference Voltage A Malfunction
P06A7 – Sensor Reference Voltage B Malfunction
P06A8 – Sensor Reference Voltage C Malfunction
Common Ford Delphi DCM 3.5 Engine ECU (2009–2015) Faults and Symptoms
The Delphi DCM 3.5 engine ECU, fitted to many Ford vehicles built between 2009 and 2015, is responsible for controlling key aspects of engine performance, emissions, and sensor communications. While widely used across the Ford range, these ECUs are prone to several well-documented faults that can cause serious running problems or even leave the vehicle completely inoperative. Below are the most common issues associated with this unit:
1. No Communications
One of the most frequent faults is a complete lack of communication with diagnostic equipment. In this situation, the ECU becomes unresponsive, making it impossible to read fault codes or carry out programming. This is usually the result of internal failures in the ECU’s circuitry.
2. Vaporizer Relay Constantly Clicking
Another common complaint is a constantly clicking vaporizer relay. This symptom points to an ECU control fault where the relay is being activated repeatedly and incorrectly. Left unresolved, this can cause further damage to components and disrupt normal vehicle operation.
3. Loss of 5V Rail to Sensors
The DCM 3.5 ECU supplies a 5V reference voltage to multiple sensors. A failure in this circuit results in the sensors being unable to operate correctly, causing the vehicle to log a range of fault codes and experience performance issues such as rough running or failure to start.
4. Common Fault Codes
When communication is possible, these ECUs often log one or more of the following diagnostic trouble codes:
P06A6 – Sensor Reference Voltage A Malfunction
P06A7 – Sensor Reference Voltage B Malfunction
P06A8 – Sensor Reference Voltage C Malfunction
These codes indicate specific failures within the ECU’s internal voltage reference circuits and almost always require specialist repair to resolve.
These issues are widely reported across Ford vehicles fitted with the Delphi DCM 3.5 ECU from 2009 to 2015, and they usually require professional intervention at ECU level to restore proper operation.
Affected Vehicles
The Delphi DCM 3.5 ECU is commonly fitted to the following Ford models between 2009 and 2015:
- Ford Galaxy (2009 – 2015)
- Ford Kuga (2009 – 2015)
- Ford Mondeo (2009 – 2015)
- Ford S-Max (2009 – 2015)
Ford Delphi DCM 3.5 ECU Repair – Essex Recons
At Essex Recons, we specialise in repairing Ford Delphi DCM 3.5 ECUs suffering from issues such as no communication, vaporizer relay clicking, 5V sensor rail loss, and fault codes P06A6, P06A7, and P06A8. Our expert technicians carry out in-depth diagnostics and component-level repairs to restore the ECU to full working order, saving you the cost of an expensive replacement. Every unit is thoroughly tested before return and supplied with warranty for peace of mind.
If your Ford is experiencing ECU problems, contact Essex Recons today for a fast, professional, and cost-effective repair service.
Affected Vehicles - Shop Now
Common Questions:
We at Essex Recons strive to exceed your expectations in the quality of our repairs. We aim to complete our repairs in a timely fashion while adhering to all ESD safety measures when working on sensitive equipment.
These units come with a lifetime* warranty.
To pay for the rebuild, simply click the product link above to select the module you require. After that, place your order directly through our website. Once your order is complete, carefully package your unit inside a sturdy box with plenty of protective material. In addition, make sure you include your contact details and order number inside the box. Then, send your package to us using a tracked courier service. As soon as we receive your unit, we will test, rebuild, and return your module, complete with your warranty.
Yes! Once an order has been placed you can drop your unit off at the following address: Unit H, OYO Business Units, Hindmans Way, Dagenham, Essex, RM9 6LN, UK. Quote your order number at the till to ensure a smooth dropoff!