B1436 — Wiper Hi/Low Speed Relay Coil Circuit Short To Battery

How much does it cost to fix B1436?

Replace an ignition coil — $150–$380; Replace spark plugs — $90–$250; Repair coil wiring or connector — $80–$250. Exact cost depends on the root cause, your vehicle and local labor rates — a proper diagnosis is the cheapest first step.

Is it safe to drive with B1436?

Drive with caution and avoid load. Ignition faults cause misfires that quickly overheat and destroy the catalytic converter; if the Check Engine Light flashes, stop and fix it first.

What is the most common cause of B1436?

The most common causes are: damaged coil wiring or connector, failed ignition coil or coil pack, faulty ignition control circuit in the ECM.

What does OBD2 code B1436 mean?

B1436 — Wiper Hi/Low Speed Relay Coil Circuit Short To Battery. A fault in the ignition system. Short, gentle driving to a shop is usually possible. Typical causes: damaged coil wiring or connector, failed ignition coil or coil pack, faulty ignition control circuit in the ECM.

What are the symptoms of B1436?

Drivers most often notice: loss of power and jerking, Check Engine Light on, hard starting, especially in damp weather, increased fuel consumption.

When your OBD2 scanner pulls code B1436, it means the engine control module has detected that the wiper high/low speed relay coil circuit is drawing too much battery voltage. In plain terms, somewhere in that circuit the wiring or a component is shorted directly to battery power when it should not be. The module watches the voltage in this circuit, and the moment it sees the signal line held at battery voltage instead of switching between ground and open, it flags B1436 and lights the check engine light. This is a body electrical fault, not an engine management one, but that does not make it trivial — the wipers are a safety system, and a short circuit can drain your battery or cause unexpected behavior at the worst moment.

The wiper circuit relies on a relay to switch the high and low speed motor windings on and off. That relay has a coil inside it, and the ECU drives the coil by grounding the circuit at the correct time. When a short to battery develops, the ECU loses its ability to control the relay properly. The module logs the fault only after confirming it occurs more than once under the same driving conditions, which is why a single glitch will not trigger the light. The freeze frame data stored alongside B1436 shows you the exact circumstances — vehicle speed, engine temperature, ignition position — when the fault was detected, and you can use those readings to recreate the failure during diagnosis.

Symptoms of B1436

• Intermittent or complete loss of wiper function in one or both speed settings
• Wipers stay on continuously and cannot be switched off
• Wipers do not respond at all when the stalk is activated
• Check engine light or body control module warning illuminated
• Battery drain if the short is present with the vehicle parked
• Clicking sound from the relay area without wiper movement

Common Causes of B1436

• Failed wiper relay with an internal short in the coil winding
• Chafed or melted wiring in the wiper circuit harness, commonly near the firewall
• Corroded or water-damaged connector at the relay or wiper motor
• Body control module fault affecting the relay ground control signal
• Aftermarket accessory wiring incorrectly tapped into the wiper circuit
• Burned or worn relay socket contacts creating an intermittent short condition

How to Diagnose B1436

1. Connect an OBD2 scanner and confirm B1436 is stored in the body control module. Record the freeze frame data — it tells you the vehicle speed, temperature, and electrical system voltage present when the fault occurred.
2. Check for any related body electrical codes. Codes in the B14xx range often appear together when there is a wiring issue that affects multiple circuits.
3. Locate the wiper relay in the power distribution center or fuse box and inspect the socket for corrosion, melting, or bent pins. The relay coil short may show as a burned contact inside the relay itself.
4. Trace the wiper circuit wiring from the relay to the motor. Look for insulation damage, pinch points from body clips, and any signs of water intrusion near the cowl or firewall pass-through.
5. Test the relay coil resistance with a multimeter if you can access it out of the socket. A shorted coil will show very low or zero resistance instead of the specified value.
6. Clear the code, operate the wipers through all functions, and verify B1436 does not return. If it does, the short is still present in the circuit.

Repair Options for B1436

• Replace the wiper hi/low speed relay — $25–$75 for the part, $50–$100 labor at an independent shop, total $75–$175
• Repair or replace damaged wiper circuit wiring harness — $80–$250 depending on the extent of the damage and whether a plug-in repair harness is available
• Replace the wiper motor assembly if the short is inside the motor windings — $80–$200 parts, $60–$120 labor, total $140–$320

Total Cost to Fix B1436

Most B1436 repairs involve a failed relay, which keeps the total cost on the lower end. Wiring damage and motor replacement push the bill toward the higher figures. At independent shop rates, expect to pay between $75 and $320 to resolve B1436. Diagnosing the circuit before replacing parts is the best way to avoid spending more than necessary.

Can You Drive with B1436?

Drive with caution. A short-to-battery fault in the wiper circuit can drain your battery overnight or cause the wipers to operate unpredictably, which is a safety concern in rain or snow. Have the circuit inspected and repaired before relying on the vehicle in bad weather.