BodyB1506

Serious

Severity: Serious - have it checked soon

Brake vacuum signal voltage is low

26 brands affected · Description from Toyota data.

Key terms: Boost pressure: extra air pressure made by a turbo or supercharger

Safety: This code relates to the braking system or brake assist. Braking may be affected.

1What it means in plain English

The brake vacuum (brake booster) signal is lower than expected, so brake assistance may be reduced.

2Common causes

Leaking brake vacuum hose or booster
Faulty brake vacuum sensor
Damaged wiring or connector
Failing vacuum pump (on engines without manifold vacuum)
Brake booster fault

3Can I drive?

Serious · drive with care

Brakes may need more pedal effort than normal. Have it checked before driving further; if the pedal feels hard or stopping distances increase, stop safely and have the car recovered.

This page gives general information. It is not professional advice. For a definite diagnosis and a repair quote, ask a qualified mechanic to inspect the car.

4Brand data 26

Brand	Code	Description	System
Ashok Leyland CV	B1506	No description available	Body
Mercedes-Benz	B1506	No description available	Body
BYD	B1506	DR. seat position sw open Brand	Body
Chery	B1506	Engine switch fault Brand	Body
Daewoo	B1506	No description available	Body
Daihatsu	B1506	Ground bracket disconnected Brand	Body
DFFS	B1506	Brake vacuum signal voltage is low Brand	Body
DFFX	B1506	DR. seat position sw open Brand	Body
Geely	B1506	DR. seat position sw open Brand	Body
GM	B1506	No description available	Body
Great Wall	B1506	DR. seat position sw open Brand	Body
Hafei	B1506	DR. seat position sw open Brand	Body
Holden	B1506	Universal Serial Bus (USB) Circuit Brand	Body
Honda	B1506	YOP ECU lost communication with MICU Brand	Body
Hyundai	B1506	No description available	Body
Land Rover	B1506	No description available	Body
Mitsubishi	B1506	DR. seat position SW open Brand	Body
Opel	B1506	No description available	Body
Perodua	B1506	Ground bracket disconnected Brand	Body
Peugeot	B1506	No description available	Body
Proton	B1506	DR. seat position SW open Brand	Body
Saab	B1506	No description available	Body
Sprinter	B1506	No description available	Body
Subaru	B1506	No description available	Body
Suzuki	B1506	Humidity Sensor Circuit Malfunction Brand	Body
Toyota	B1506	Brake vacuum signal voltage is low Brand	Body

Legend: SAE is the generic J2012 description; Brand is text taken from that manufacturer’s data. Manufacturer rows keep the wording and language of the source data, and non-English text is tagged so screen readers pronounce it correctly.

5Extended variant codes 6

These 7-character codes are manufacturer-specific variants of B1506 and may be reported by some scan tools.

Brand	Code	Description	System
Mahindra	B150611	FL Door Handle Output Short To Gnd Brand	Body
Mahindra	B150615	FL Door Handle Output Short To Batt / Open Brand	Body
Mercedes-Benz	B15062A	No description available	Body
Sprinter	B15062A	No description available	Body
Mercedes-Benz	B150647	No description available	Body
Sprinter	B150647	No description available	Body

6Related codes

Browse Bxxx codes or B150xx codes.