B3198

Code

Generic B — Body

Keyless Entry Antenna Circuit Malfunction

Brand: Generic

Type: B — Body

Views: UK: 4 EN: 15 RU: 8

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Damaged or disconnected keyless entry antenna
Broken, chafed or corroded wiring harness or connector
Open or short in the antenna feed/ground circuit
Failed antenna driver/relay or body control module (BCM) output
Water intrusion or corrosion at antenna or connector
Faulty or depleted key fob battery or defective key fob (false trigger)

Symptoms

Keyless entry (lock/unlock/present) does not work or is intermittent
Door(s) only respond at close range or not at all
Keyless entry warning or key-inhibit indicator illuminated
Remote functions work sporadically or require multiple attempts
Other related body/CAN network functions may log additional errors

What to check

Scan vehicle for B3198 and any other body/immobilizer/BCM codes; record freeze frame and occurrence count
Verify spare key fob(s) and check/replace key fob battery to rule out transmitter faults
Visually inspect antenna location(s), connectors and wiring for corrosion, water ingress, damage or poor routing
Check related fuse(s) and relays powering the antenna/BCM circuits
Attempt remote functions while observing antenna connector/wiring for intermittent behavior (wiggle test)
Use a scan tool to monitor BCM status and to actuate keyless entry outputs if supported

Signal parameters

Antenna circuit should show continuity with no short to battery or ground when measured between antenna connector pins and BCM reference
Power feed to antenna (if applicable) should show battery voltage or switched supply when the system is active
When commanded, the BCM should provide a drive/pulse or enable signal to the antenna circuit (check with scan tool or oscilloscope if available)
BCM should report keyless entry attempts and antenna status over vehicle network (CAN/LIN) without repeated error bursts

Diagnostic algorithm

Confirm fault: read B3198 and related codes with a capable scan tool; clear codes and attempt to reproduce.
Key fob check: verify operation with a known-good/spare fob and replace fob battery. Re-scan for code reappearance.
Visual inspection: locate antenna(s) (commonly in door pillars, roof headliner, rear deck or bumper), inspect connectors and wiring for damage, corrosion or water entry.
Power/ground check: verify fuses, ground connections and supply voltage to the antenna/BCM circuit; repair any poor grounds or blown fuses.
Continuity/short test: disconnect the antenna connector and check continuity to the BCM connector pins; check for shorts to ground or battery. Repair wiring or connector issues found.
Module output test: with scan tool, command keyless functions and observe for drive/enabling signal at the antenna connector; use an oscilloscope for RF/carrier checks if available.
Isolation: if wiring and supply are good, replace antenna assembly and retest. If fault persists, suspect antenna driver or BCM — verify BCM power/grounds and check for software updates or reprogramming requirements.
Finalize: after repairs clear codes, perform multiple function tests and a road/test-area verification of keyless operation; confirm no reoccurrence of B3198.

Likely causes

Loose or corroded antenna connector
Open or shorted antenna wiring near an access point (door pillar, rear trim)
Faulty antenna element or mounting damage
Weak/failed key fob battery causing repeated attempts and antenna faults

Fault status

⚠️ Status

Keyless entry antenna circuit malfunction detected by BCM. Fault may be caused by open/short/intermittent antenna circuit, connector or module driver. Stored fault requires wiring, antenna or module inspection/repair.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 1.0-3.0 hours