P1682 Cadillac Code - Ignition 1 Switch Circuit 2
Quick Answer
There are 2 ignition 1 voltage circuits supplied to the Engine Control Module (ECM). Common causes include Faulty ignition switch, Ignition Switch harness is open or shorted, Ignition Switch circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P1682 Cadillac indicates Ignition 1 Switch Circuit 2.
- Common causes
- Common causes include Faulty ignition switch, Ignition Switch harness is open or shorted, Ignition Switch circuit poor electrical connection.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code P1682 Cadillac Description
What are the Possible Causes of the DTC P1682 Cadillac?
- Faulty ignition switch
- Ignition Switch harness is open or shorted
- Ignition Switch circuit poor electrical connection
- Faulty Engine Control Module (ECM)
How to Fix the DTC P1682 Cadillac?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P1682 Cadillac code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80β$150 per hour; dealerships and metro areas may be higher, independents may be lower.
Need more information about the P1682 Cadillac code?
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Frequently Asked Questions about P1682 Cadillac Code
No Frequently Asked Questions about P1682 Cadillac Code found.
Discuss the causes and fixes for P1682 Cadillac OBDII Code
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I have p1682 and the car will not start. I just changed the water pump, thermostat and power steering pump. I had to remove the intake and the water pump manifold. I think I might have left something unplugged. Were do I begin to find it. I have checked everywhere.
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Hello. Let me check for more information. What model and year is your vehicle?
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Start with the battery terminals. Make sure the battery terminals are clean and tight. If the battery is OK, then the next step based on the P1682 code, is to try swapping or replacing the Powertrain Control Module (PCM) relay.

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Have P1682 code on 2013 CTS and can't clear the code get no crank or start. What could be the issue? have checked all fuses and changed starter relay but get no crank or start
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Unfortunately, I haven't had that problem, but according to a national database of repairs for your model year, the Ignition Switch is the most probable cause of your problem.
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thanks will have to take it somewhere to get that done. beyond my expertise.
Also saw possible fuel pump module ecm issues as possible causes. hoping for cheapest repair
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