Mazda CX5 - error code P0471 and poor starting and acceleration behaviour

Data sheet
Manufacturer	Mazda
Vehicle model	CX5 GH/KE with automatic transmission
Engine	2.2 16V CDI Skyactiv-D
Engine code	SH-Y4
Year of manufacture	2013-2017
Symptoms	Poor starting and acceleration behaviour Vehicle goes into emergency mode Error code: P0471

Technical information and practical tips have been compiled by HELLA in order to provide professional support to vehicle workshops in their work. The information provided on this website is intended for use by suitably qualified personnel only.

"SCBS forward gear malfunction" is displayed on the instrument cluster

If the error message "SCBS / City emergency stop assistant forward gear malfunction" is displayed on the instrument cluster on the vehicle models mentioned above, one cause for this may be a defective boost pressure sensor. The faulty signal can cause error entries in different control units. In addition, the warning lamps for tyre pressure control, parking brake, I-Stop system and ABS may light up simultaneously. The error can be reset briefly by switching the ignition off and on, but usually reappears after a short driving time.

Control unit diagnostics The following error codes may be stored in various system control units for this cause.

Comfort control unit

CAN connection for distance control system – signal implausible

ABS control unit

U0401 CAN-BUS – Invalid data

Engine control unit

P0471 Exhaust pressure sensor 1 (boost pressure sensor) – function faulty

Repair advice Continuing to drive with this defect can damage the engine. In addition, the deficiency causes hard shifting behaviour in vehicles with automatic transmission. The vehicle manufacturer replaced the exhaust pressure sensor with a new modified component. Within the scope of the repair, it must therefore be ensured that the old defective sensor is replaced by a new modified sensor (repair kit). After the repair, the relevant error memory entries in the relevant control units must be deleted.

Spare parts information Exhaust gas pressure sensor old: Mazda SH02-BK-5204 Exhaust pressure sensor new: Mazda SHY6-18-W00

This defect may also occur in other vehicle models with the same type of engine and transmission equipment.

Mazda CX5 SCBS Forward gear malfunction error message P0471 — Warning on the instrument cluster

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