Engine & fuel system
2 documented faults — symptoms, causes and workshop fixes.
Engine cuts out intermittently
Symptoms
Intermittent power loss. Poor cold starting.
Cause
Fuel pressure regulator control solenoid faulty.
Repair
- Fit new fuel pressure regulator control solenoid.
Parts1 part
| Part | Part number | Qty |
|---|---|---|
| Fuel pressure regulator control solenoid (Denso) | 294009-0120 | 1 |
Data: Motorwise Workshop. Bulletin 1.
Excessive oil consumption
Poor sealing of fuel injectors allowing blow-by gas ingress into engine oil. Fix: fit a new part.
Overview
- Affects
- All models with MZR-CD (RF-Turbo) engine code.
- Remedy
- Fit new part
Symptoms
Carbon deposit build up in engine.
Repair steps
- Remove fuel injectors. Thoroughly clean all mating surfaces.
- Fit new copper washer to fuel injector.
- Install fuel injectors. Ensure fuel injector retaining bolt tightened to correct torque setting.
- Flush engine oil system with a suitable flushing oil.
- Change engine oil and filter.
Data: Motorwise Workshop. Bulletin 4.
Electrical & ignition
1 documented fault — symptoms, causes and workshop fixes.
SRS warning lamp illuminated
Symptoms
Trouble codes stored in SRS control module fault memory: B2856, B104D, B2227.
Cause
Water ingress into crash sensor wiring harness multi-plug.
Repair
- Fit modified crash sensor.
Parts1 part
| Part | Part number | Qty |
|---|---|---|
| Crash sensor | C2Y5 57 K1X, or C235 57 K1XB | 1 |
Data: Motorwise Workshop. Bulletin 2.
Suspension & drivetrain
1 documented fault — symptoms, causes and workshop fixes.
Knocking noise from rear of vehicle when driving over rough roads
Rear suspension spring upper rubber insulation cup adrift caused by protruding welding bead. Fix: fit a modified part.
Overview
- Affects
- All models.
- Remedy
- Fit modified part
Repair steps
- Check if rear suspension spring upper rubber insulation cup displaced.
- Remove rear suspension spring and upper rubber insulation cup.
- Reduce height of welding bead at rear suspension spring upper mating surface.
- Fit modified rubber insulation cup to rear suspension spring.
- Fit rear suspension spring.
Parts
| Part | Part number | Qty |
|---|---|---|
| Rubber insulation cup | C2Y6-28-012 | As required |
Data: Motorwise Workshop. Bulletin 3.
Glossary
Technical terms used in this guide.
- Trouble Codes
- Standardised fault codes stored by the engine control module, read with a diagnostic tool
- SRS
- Supplementary restraint system — the airbags and seat-belt pretensioners
- Control Module
- A control unit for one of the vehicle's systems (engine, gearbox, brakes, body, and so on)
- Crash Sensor
- A sensor that detects an impact and can trigger the alarm or airbags
- Fault Memory
- The list of stored trouble codes in a control module
- Multi-Plug
- A multi-pin electrical connector on a wiring harness
- Solenoid
- An electrically operated valve or actuator
- Wiring Harness
- The bundled cables that carry power and signals around the vehicle
Frequently asked questions
What are the common faults with the Mazda 5 2.0 CRD?
This guide contains four workshop bulletins for the Mazda 5 2.0 CRD. Of these, two concern the engine and fuel system and one the electrical and ignition. Symptoms, causes, repair steps and part numbers are shown where supplied.
Does every Mazda 5 2.0 CRD have these faults?
No. These are patterns documented across the model by workshops, not predictions for an individual vehicle. Where a fault applies only to certain vehicles or VIN ranges, that is listed with the fault.
Can I check for Mazda 5 2.0 CRD faults myself?
Many of them. The documented symptoms can be seen, heard or felt during a test drive.