What Does B1377 Mean?
This code indicates that the Body Control Module (BCM) has detected a malfunction in the oil change reminder lamp circuit. The BCM monitors the electrical circuit that controls the oil change indicator light on the instrument cluster and has identified an open circuit, short circuit, or excessive resistance. This is a manufacturer-specific code related to the maintenance reminder system, not the actual oil pressure or condition.
Common Causes
35%
Failed oil change indicator lamp bulb or LED in the instrument cluster
30%
Open or short circuit in wiring harness between BCM and instrument cluster
20%
Faulty instrument cluster circuit board or display module
10%
Corroded or loose connector terminals at instrument cluster or BCM
5%
Failed Body Control Module with internal driver circuit fault
Diagnostic Steps
1
Step 1: Perform visual inspection of the instrument cluster to verify if the oil change lamp illuminates during key-on bulb check. Note whether the lamp fails to light up completely or behaves abnormally
2
Step 2: Disconnect the instrument cluster connector and inspect pins for corrosion, bent terminals, or moisture. Clean and repair any damaged pins and apply dielectric grease before reconnecting
3
Step 3: Using a digital multimeter, backprobe the oil change lamp circuit wire at the instrument cluster connector while commanding the lamp ON via scan tool bi-directional controls. Check for battery voltage (lamp control) or ground signal depending on manufacturer design
4
Step 4: If voltage/ground signal is present at the cluster connector, test the lamp bulb or LED by removing the instrument cluster and checking continuity across the lamp terminals. Replace bulb or LED assembly if open circuit is found
5
Step 5: If no voltage/ground signal is present at cluster, trace wiring back to BCM connector and check for opens, shorts to ground, or shorts to voltage using multimeter continuity and resistance tests
6
Step 6: Clear codes, cycle ignition, and verify proper lamp operation. Test lamp function using scan tool actuation commands and confirm code does not return after multiple drive cycles
Estimated Repair Cost
$75 - $450
Parts + labor, varies by vehicle and location
This code indicates that the Body Control Module (BCM) has detected a malfunction in the oil change reminder lamp circuit. The BCM monitors the electrical circuit that controls the oil change indicator light on the instrument cluster and has identified an open circuit, short circuit, or excessive re...
The most common cause of B1377 (Oil Change Lamp Circuit Failure) is: Failed oil change indicator lamp bulb or LED in the instrument cluster
Typical repair costs for B1377 range from $75 to $450, depending on the vehicle, location, and whether you do it yourself or go to a shop.
This code does not affect vehicle safety or drivability and the vehicle can be driven normally. The only impact is the loss of the oil change reminder function, which may result in missed maintenance intervals if the owner does not track oil changes manually.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to B1377 to identify the root cause.
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Quick Info
Category
Body
System
Body Control and Instrument Cluster
Difficulty
Type
Manufacturer
Recommended Tools
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