B1302 is triggered when monitoring logic identifies an issue with Accessory Delay Relay Coil Circuit Failure affecting body electronics and comfort modules.
B1302 Code: Meaning, Symptoms, Causes & Fix
Overview
Symptoms
- related warning lamp illuminated
- battery draw complaints
- feature inoperative intermittently
Common causes
- Open circuit in wiring affecting accessory delay relay coil circuit failure
- Broken terminal inside harness
- Connector pin damage/corrosion or harness stress near related components
How to diagnose B1302
- Confirm B1302 and capture freeze-frame data with a professional scan tool.
- Inspect wiring, connectors, and grounds related to accessory delay relay coil circuit failure for obvious defects.
- Use a continuity test from module pin to component to identify opens/high resistance.
- Check for related DTCs to identify the root-cause chain before replacing parts.
- After repair, clear codes and confirm readiness monitors complete without recurrence.
Severity of code B1302
Moderate: This code is moderate severity: the vehicle may still operate, but fault progression can increase repair cost over time.
Can you drive with B1302?
Most vehicles can be driven short-term with B1302, but postpone heavy load/highway driving until repaired.
If the warning lamp is flashing or drivability/safety is affected, avoid driving and diagnose immediately.
How to fix it (step-by-step)
- Repair obvious wiring/connector faults first to prevent repeat parts replacement.
- Address the root fault mode (open) in the accessory delay relay coil circuit failure circuit/system.
- Apply the required relearn/adaptation procedure if specified by service information.
- Road-test and verify B1302 remains cleared under the conditions that originally set the code.
Fix options
- Repair open circuit and secure connector lock.
- Clear corrosion and protect terminals.
- Clear DTCs and verify with live data and completed drive cycle.
Typical repair cost
$160-$850
Common mistakes when diagnosing B1302
- Replacing parts without verifying voltage, ground, and signal integrity first.
- Ignoring related stored/pending codes that indicate upstream faults.
- Skipping post-repair verification drive cycle and readiness checks.
B1302 in common vehicles
B1302 appears across makes such as Ford, Toyota, Honda, Chevrolet. Failure patterns differ by platform: wiring routes, software calibration, and component supplier revisions can change root cause.
Frequently asked questions
What causes B1302?
B1302 is commonly set by open faults affecting accessory delay relay coil circuit failure.
How much does it cost to fix B1302?
For B1302, repair costs are typically $160-$850 depending on exact root cause, labor rates, and part quality.
Can I clear B1302 without repair?
You can clear B1302 temporarily, but the code usually returns until the underlying fault is corrected.