What Does B1436 Mean?
This code indicates the Body Control Module (BCM) has detected an unintended voltage (battery voltage) on the wiper hi/low speed relay coil control circuit. The BCM monitors the relay coil circuit and sets this code when it detects a short to battery voltage instead of the expected ground or switched control signal. This condition prevents proper wiper speed control and may cause wipers to operate continuously or at incorrect speeds.
Common Causes
45%
Damaged or chafed wiring harness causing short to battery voltage between BCM and wiper relay
30%
Faulty wiper hi/low speed relay with internal short to power
15%
Corroded or damaged connector terminals at relay or BCM creating cross-circuit short
10%
Failed Body Control Module with internal driver circuit fault
Diagnostic Steps
1
Step 1: Perform visual inspection of wiper relay location, wiring harness routing from BCM to relay, and all connectors for visible damage, chafing, melted insulation, or corrosion. Pay special attention to areas where harness contacts body panels or passes through grommets.
2
Step 2: Disconnect wiper hi/low speed relay and measure voltage at relay coil control terminal (BCM side) with ignition on. Expected reading: 0-2V (ground or low voltage control). If battery voltage (12V+) is present with relay disconnected, wiring harness has short to power.
3
Step 3: Using wiring diagram, disconnect BCM connector and check continuity between relay coil control circuit and battery voltage circuits. Should read infinite resistance (open circuit). Any continuity indicates harness short requiring repair or replacement.
4
Step 4: If wiring tests good, test suspect relay by measuring coil resistance (typically 70-120 ohms) and check for internal shorts between coil and power terminals using ohmmeter. Replace relay if out of specification or shows short.
5
Step 5: Reconnect all components, clear codes, and operate wiper system through all speed ranges. Monitor live data for relay control status and verify proper BCM command signals during operation to confirm repair.
Estimated Repair Cost
$100 - $450
Parts + labor, varies by vehicle and location
This code indicates the Body Control Module (BCM) has detected an unintended voltage (battery voltage) on the wiper hi/low speed relay coil control circuit. The BCM monitors the relay coil circuit and sets this code when it detects a short to battery voltage instead of the expected ground or switche...
The most common cause of B1436 (Wiper Hi/Low Speed Relay Coil Circuit Short To Battery) is: Damaged or chafed wiring harness causing short to battery voltage between BCM and wiper relay
Typical repair costs for B1436 range from $100 to $450, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Vehicle is safe to drive, but wiper functionality may be compromised which creates significant safety risk during inclement weather. Repair should be completed before driving in rain or snow conditions.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to B1436 to identify the root cause.
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Quick Info
Category
Body
System
Wiper/Washer System
Difficulty
Type
Manufacturer
Recommended Tools
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