Does P1682 mean my ignition switch failed?

It identifies an ignition-switch circuit, not a confirmed failed switch. The cited GM truck example involves a connector connection. The actual wiring and circuit tests determine whether the switch, connection or another part of the monitored path needs repair.

Why did the codes return after a MAF replacement?

GM documents that service history in a particular truck condition. The specified connection may be involved, but it must be inspected. If the connection defect is absent, the bulletin requires further diagnosis before another sensor is selected.

Is the X3-H6 connection the first place to check on every GM vehicle?

No. That reference belongs to the listed Silverado/Sierra application. Have the vehicle and engine matched to the bulletin and wiring information before a technician uses its connector or terminal identification.

Can a connection repair still require parts?

Yes. The bulletin includes a connection component in its parts section. A wiring repair can require the correct terminal, lead or related material; the failed finding and applicable repair instructions determine the job.

Can I keep driving with P1682?

The code alone does not establish safe travel. Arrange diagnosis and follow the handbook and current warnings. If the engine stalls, will not restart, runs unpredictably or loses power unsafely, stop safely and obtain assistance instead of trying to reproduce the fault on the road.

How much does fixing P1682 cost?

Ask for an itemized estimate based on the actual circuit diagnosis. It should separate diagnostic work, any required connection or component repair, and verification. The code and the example bulletin do not establish a standard cost or a guaranteed labor-to-parts split.

OBD-II trouble code

P1682: GM P1682 — Ignition 1 Switch Circuit 2

Application matters: This guide covers GM’s Ignition 1 Switch Circuit 2 description. A circuit name is not a diagnosis of the ignition switch. The cited truck bulletin identifies a possible connector fault and requires further vehicle-specific diagnosis if that fault is not found. Connector locations and repair methods must be matched to the actual vehicle.

GM’s ignition-circuit report. A documented truck example involves a connector terminal, but the code alone does not identify a failed switch, sensor or controller.

Medium severityPowertrainPCM / ElectronicsAssess symptoms before driving

Quick facts

System: Powertrain
Category: PCM / Electronics
Severity: Medium severity
Driving guidance: Depends on symptoms and vehicle guidance
Repair cost range: Get a vehicle-specific estimate after diagnosis.
DIY difficulty: Shop recommended

A code alone cannot establish whether driving is safe. Stop safely for a red brake or oil-pressure warning, overheating, severe misfire, stalling, or impaired braking or steering, and follow the owner's manual. Restraints faults can reduce crash protection even when the vehicle runs normally.

Browse every code in Powertrain, or start from the full code library.

What does P1682 mean?

GM describes P1682 as Ignition 1 Switch Circuit 2. Preserve that full circuit designation when obtaining service information. The words switch circuit do not establish that the ignition switch has failed, nor do they identify which connector or control unit needs work.

Bulletin 21-NA-032 provides a specific example on listed Silverado and Sierra 1500 trucks. A compromised wire-to-terminal connection at the underhood electrical center can accompany P1682 and P0101. Other listed companion codes include P0689, P16A7 and P16BC. A previous MAF replacement is relevant service history, but it does not by itself establish the present cause.

The bulletin’s decision is conditional: inspect the specified connection and repair it when the defect is observed. If no problem is found there, continue the applicable code diagnosis before replacing the MAF sensor. The repair can involve a terminal or connection component; describing it as a repair with no parts would be misleading.

The covered vehicles are the 2019 new-model and 2020–2021 Silverado 1500 and Sierra 1500 with the listed L82/L84 5.3L and L87 6.2L engines. X3-H6 is an application-specific location. It must not be transferred to a different fuse block, model or engine just because the same code is present.

Use the actual wiring and diagnostic procedure to establish what the monitored circuit connects to and which checks come first. The bulletin does not create a universal explanation that an unstable controller reference caused every airflow code. Companion codes can guide the investigation while still requiring separate confirmation after repair.

Possible causes

A compromised dual-crimp or wire-to-terminal connection in the specifically covered GM underhood electrical-center example
Another wiring or terminal defect established in the vehicle’s monitored ignition-circuit path
A supply, switching or controller-related fault only where the matched circuit diagnosis supports it

Symptoms

Service Engine Soon or check engine light with P1682 stored
A warning that illuminated previously and is now off while a history code remains
Companion P0101, P0689, P16A7 or P16BC in the covered truck example

Diagnostic steps

Save the full scan report, code status, and available freeze-frame data before clearing anything. Confirm the reporting module, any failure-type suffix, and the procedure for the exact vehicle. The steps below are an overview; use manufacturer specifications and safety procedures for testing.

1.Record the complete scan and which codes are current or historical. Report warning changes, actual running symptoms and any previous sensor or electrical repair.
2.Match the vehicle, engine and wiring information before using a connector or cavity reference. Check whether GM 21-NA-032 applies to the particular truck.
3.On an applicable vehicle, have a qualified technician inspect the specified connection and compare it with the bulletin’s defect examples. Leave connector access, isolation and terminal handling to the matched safe procedure.
4.Repair a demonstrated connection defect with the required terminal or service component. Do not assume that the bulletin means no replacement material is needed.
5.If that defect is absent, continue the vehicle-specific P1682 and companion-code diagnosis. Do not repeatedly replace the MAF, or rank the ignition switch last, solely from this example.
6.Use protected professional circuit tests specified for the identified system. Do not jumper a feed, add an improvised load or move a live harness to provoke the fault.
7.Recheck the repaired circuit and each remaining code through the appropriate verification. A companion code that persists can need its own diagnosis rather than another copy of the same repair.

Repair cost

Get a vehicle-specific estimate after diagnosis.

A trouble code alone does not price the repair. Ask the shop to identify the confirmed fault and itemize diagnosis, parts, labor, programming or calibration, and taxes.

Estimate your repair

Run the numbers for your vehicle

Open the Repair Cost Estimator with wiring harness / circuit repair, if diagnosed preselected. Adjust labor rate and vehicle category to fit your situation.

Estimate your repair cost

Related repairs

These links are planning examples; the code does not confirm that any listed part has failed.

Wiring harness / circuit repair, if diagnosed Check engine light diagnosis Mass airflow sensor replacement, only if separately diagnosed

DIY vs shop

A qualified shop is recommended because this can involve control module programming and configuration, which generally needs manufacturer software and a stable supply throughout. Ask the technician what testing confirmed the repair.