B1654

Code

Other B — Body

Seat Driver Recline Backward Circuit Short To Ground

Brand: Other

Type: B — Body

Views: UK: 18 EN: 33 RU: 22

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Damaged or chafed wiring harness contacting chassis ground
Corroded or loose connector at the recline motor or seat control module
Shorted motor winding or internal short inside recline actuator
Faulty seat control module or grounding point
Water intrusion or contamination in seat connectors or switches
Aftermarket seat components or previous repairs with incorrect wiring

Symptoms

Driver seat will not recline backward or moves only in one direction
DTC B1654 stored in body/seat control module and may reappear after clearing
Intermittent or no response when using recline switch
Blown fuse related to seat motor (on some vehicles)
Possible related warnings on instrument cluster or SRS/airbag system if seat position info is used by those systems

What to check

Read and record all stored codes and freeze frame data from body/seat modules
Visually inspect seat wiring harness, connectors, and grommets at base of seat and where harness passes through the floor
Check for corrosion, bent pins or pushed-out terminals at the recline motor connector and seat control module connector
Inspect seat mounting grounds and ground straps for tightness and corrosion
Attempt to operate recline while monitoring live data (module outputs, switch states)
Check fuses/relays for the seat motor circuit

Signal parameters

With ignition ON and recline NOT commanded: circuit to motor should show high resistance to chassis ground (open/very high kΩ)
When recline backward is commanded: module should apply approx. battery voltage (near 12 V) to the motor feed for the commanded polarity; reverse polarity or separate feed for forward direction may be used by some systems
Motor winding resistance (vehicle-specific): typically low ohms (hundreds of milliohms to a few ohms) between motor terminals; there should NOT be low resistance from either motor terminal to chassis ground (should be high kΩ)
If a short-to-ground exists measured voltage at the command output will be near 0 V when commanded and continuity to ground will be present

Diagnostic algorithm

Safety first: follow vehicle manufacturer procedures for disabling SRS/airbag circuits before working on seat wiring; disconnect battery if required and wait the specified time.
Read and save all codes from all modules; note any other related B- or U-codes.
Attempt seat recline while observing live-data: verify switch inputs and module output commands. Note whether command is present when switch is operated.
Visually inspect harness routing under the seat, through carpet grommet, and at seat frame for abrasion, pinching, or impact damage.
Unplug the recline motor connector. With ignition ON and command active, measure voltage at the control module output connector while an assistant operates the switch. If voltage appears at the module output but not at the motor connector, suspect harness/connector fault.
With harness disconnected from both ends, perform an ohm/continuity test from the motor power pins to chassis ground. Low resistance indicates a short to ground. Expected: motor terminals should NOT be shorted to ground (verify vehicle-specific values).
Inspect and test the motor directly: measure winding resistance between motor terminals (compare to spec), and measure each terminal to motor housing (should be open/high resistance).
If motor/actuator checks good, inspect and repair wiring between the module and motor: repair chafed insulation, replace damaged sections, and clean/replace corroded connectors/terminals. Verify ground points and clean/tighten.
If wiring and motor are good, test or swap seat control module (if serviceable) or perform further module-level diagnostics per manufacturer procedures.
After repairs, clear codes, operate seat through full range and monitor for reappearance of the code. Road-test or cycle ignition and retest as required.

Likely causes

Pinched harness at seat base or seat belt anchor causing insulation abrasion to ground
Connector terminal pushed out or bent, contacting seat frame
Recline motor internal fail creating low-resistance path to ground
Corroded ground strap or body ground at seat mounting

Fault status

⚠️ Status

Stored code indicates a short circuit to ground on the driver seat recline (backward) circuit. The seat may not move rearward; an electrical fault in wiring, connector, motor, or control module is present.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 0.5-2.0 hours