B3717 – Front Wiper Relay Drive Circuit Low (BCM)

System: Body | Standard: ISO/SAE Controlled | Fault type: Circuit Low

Definition source: SAE J2012 naming/structure guidance

What Does B3717 Mean?

B3717 – Front Wiper Relay Drive Circuit Low (BCM) is an ISO/SAE controlled body system DTC that indicates the Body Control Module (BCM) has detected a circuit low condition on the front wiper relay drive circuit. In other words, the BCM monitors the electrical line it uses to command (drive) the front wiper relay, and it has determined the signal level on that circuit is lower than expected for the current operating state.

A “circuit low” fault points to an electrical condition such as a short to ground, excessive voltage drop, or an abnormal load on the relay drive circuit. This code does not, by itself, prove the relay or BCM is defective; it confirms the BCM observed a low electrical condition on the specific relay drive circuit it monitors.

Quick Reference

• Code: B3717
• Official Title: B3717 – Front Wiper Relay Drive Circuit Low (BCM)
• System: Body
• Standard classification: ISO/SAE Controlled
• Fault type: Circuit Low
• What it indicates: BCM detected the front wiper relay drive circuit is lower than expected
• Most affected function: Front windshield wiper relay control (wiper operation may be reduced or inoperative)
• Tools that help: Scan tool with BCM access, wiring diagram, digital multimeter, test light, back-probing tools

Symptoms

When B3717 is present, symptoms are related to front wiper operation because the BCM’s relay drive circuit is involved in controlling the front wiper relay.

• Front wipers inoperative: wipers do not run in any switch position
• Intermittent operation faults: intermittent mode fails or is inconsistent
• Incorrect response to switch commands: the wipers do not operate as commanded
• Unexpected stopping: wipers may stop during operation
• Wiper park concerns: wipers may not return to the normal parked position
• Stored BCM DTC: B3717 present when scanned (with or without an on-dash indicator, depending on the vehicle)

Common Causes

Because B3717 is a circuit low fault for the front wiper relay drive circuit, root causes typically involve the relay control wiring, terminals, the relay coil/load characteristics, or BCM driver conditions.

• Short to ground in the front wiper relay drive circuit wiring
• Open or high resistance in the relay drive circuit causing abnormal low signal behavior under command/monitoring
• Corrosion or moisture at the relay socket, inline connector, or BCM connector leading to voltage drop
• Poor terminal tension or damaged terminals (spread, backed-out, or overheated pins) at the relay or BCM connection points
• Front wiper relay fault (coil or internal issue that creates an abnormal load on the drive circuit)
• Power supply or ground issues affecting the control side of the relay/BCM circuit operation (including fuse/relay feed or ground integrity issues)
• BCM internal driver issue affecting the front wiper relay drive circuit (verify with circuit isolation tests before considering module replacement)

Diagnosis Steps

Use the correct wiring diagram for the vehicle configuration. Relay drive strategies vary (for example, how the BCM drives and monitors the relay), so confirm the exact terminal IDs and expected values from service information before final conclusions.

1. Confirm the DTC and capture data: Scan the BCM for B3717 and any additional body/wiper-related codes. Record DTC status information (current/history) and any available failure records.
2. Verify the symptom: Operate the front wipers through all commanded modes available from the switch. Note whether the relay clicks (if audible), whether the wipers move, and whether the fault is constant or intermittent.
3. Check basic electrical condition: Verify battery voltage and overall electrical system stability. A low system voltage condition can contribute to low readings and should be corrected before deeper circuit evaluation.
4. Inspect fuses and the relay location: Inspect related fuses and the front wiper relay socket area for signs of water intrusion, heat damage, corrosion, or loose fit. Confirm the correct relay is installed in the correct cavity.
5. Visual inspection of the relay drive circuit: Inspect the harness routing between the BCM and the relay/fuse block area. Look for chafing, pinched sections, damaged insulation, or prior repairs that could contact ground.
6. Command the relay ON and check the drive circuit level: With a scan tool output control (if supported) or by operating the wiper switch, measure the electrical level at the relay drive circuit. Compare observed behavior to service information for the circuit’s expected state when commanded ON and OFF.
7. Check for a short to ground: With the relay removed (and ignition state per service instructions), measure resistance from the relay drive circuit to chassis ground. A low resistance reading indicates an unwanted ground path. Wiggle the harness during the test to locate intermittent contact.
8. Voltage drop and load testing: If the circuit appears to have continuity but still faults, load-test the drive circuit and related terminals. A multimeter may show voltage with no load even when the circuit cannot carry current properly. Use an appropriate test light or specified load method to reveal high resistance connections.
9. Test the front wiper relay: Verify the relay coil is not internally shorted and that it operates correctly. If service procedures specify coil resistance or functional checks, compare results to specification.
10. Connector and terminal integrity checks: Inspect BCM connector pins and relay socket terminals for corrosion, spread terminals, pushed-back pins, or poor retention. Repair terminal fit issues as required and ensure connectors fully seat and lock.
11. Isolate the BCM driver if needed: If downstream wiring and the relay test good, disconnect the affected circuit per service guidance and retest the BCM output. If the drive circuit remains low with the downstream load disconnected, further BCM pin-level testing is warranted to confirm an internal driver concern.
12. Clear and verify: Clear DTCs, cycle ignition as required, then operate the wipers through multiple modes. Rescan to confirm B3717 does not return and that normal wiper operation is restored.

Possible Fixes

• Repair wiring damage in the front wiper relay drive circuit (short-to-ground, open, or high resistance section)
• Clean and correct connector issues at the relay socket, inline connectors, or BCM connector (corrosion removal per service method, terminal repair/replacement, ensure proper pin fit)
• Replace the front wiper relay if testing confirms the relay is faulty and creating an abnormal load or incorrect operation
• Restore proper power and ground integrity for the related control circuit components (repair poor grounds, correct feed issues, address fuse/terminal damage)
• Repair or replace the BCM only after circuit tests confirm the BCM driver output is low with the circuit properly isolated and all external causes have been ruled out, following applicable service procedures

Can I Still Drive With B3717?

Driving with B3717 is not an engine performance issue, but it can be a visibility and safety issue because it involves the front wiper relay drive circuit. If the BCM detects the drive circuit is low, the front wipers may be unreliable or inoperative.

If there is any chance of rain, fog, snow, or road spray, the vehicle should not be relied on until front wiper operation is confirmed to be consistent. If wipers are not functioning correctly, address the fault before driving in conditions that require windshield clearing.

Last updated: March 22, 2026