OBD Code B1475: Accessory Delay Relay Contact Short To Battery

Q: What does OBD code B1475 mean?

Accessory Delay Relay Contact Short To Battery. The accessory delay relay contact is electrically stuck to the battery voltage instead of switching properly. Think of it like a light switch that's jammed in the 'on' position and won't turn off.

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What This Actually Means

In plain language — no jargon

The accessory delay relay contact is electrically stuck to the battery voltage instead of switching properly. Think of it like a light switch that's jammed in the 'on' position and won't turn off.

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Symptoms You May Notice

3 known symptoms for this code

Accessories (windows, locks, seats) stay on or behave erratically

Battery drains quickly when vehicle is off

Multiple accessory functions fail to respond to commands

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Embedded Systems Insight

What the ECU/ECM is actually computing

The ECU monitors the accessory delay relay control circuit for proper voltage switching between ground and battery. It detects when the relay contact is shorted directly to battery voltage instead of cycling on and off as commanded, indicating a welded or stuck relay contact.

Voltage & Parameter Thresholds

Parameter	Normal Range	Fault Condition
Relay Contact Voltage	0V (off) to 12V+ (on) with proper switching	Continuous 12V+ when command is for off-state
Control Signal Response	Relay activates/deactivates within 200ms of command	No change in relay state despite command signal

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Diagnostic & DIY Fix Guide

Check these in order — from cheapest to most complex

1

Accessory Delay Relay

Locate relay in fuse/relay box, remove and install replacement relay.

2

Relay Connector

Inspect connector pins for corrosion or damage and clean with electrical contact cleaner.

3

Wiring Harness

Check relay circuit wiring for shorts to battery voltage and repair or replace damaged insulation.