2018 GMC Sierra 1500 Engine Won't Shut Off

[Dr.Toetags]

I have a 18' Sierra 1500 and randomly in the middle of the day it decided to not shut off the motor. When I turn the key back all the interior electrics go off except the motor and blower (as if I auto started the truck). I have searched the Internet thoroughly and it seems this is a hard issue to find a definite solution to. If anyone has any information to point me in the right direction would be greatly appreciated. I am also throwing 3 random codes with a check engine light, P0700, P1682, and P0561. ANYTHING AT THIS POINT WOULD HELP!!!!!

[BO TIE 1]

Good place to start is at the battery. These trucks do some crazy things when the batteries start going bad. Is it the original battery? You can get it tested at a lot of parts stores usually for free. 

[Dr.Toetags]

Just had a new battery installed and that did not fix my issue. I am at a loss here on what the issue is...

[rav3]

Have you checked for any codes?

[asilverblazer]

Circuit/System Description

There are 2 ignition voltage circuits supplied to the engine control module (ECM). One is supplied by the engine controls ignition relay, and the other is supplied by the ignition main relay. The ECM monitors and compares the ignition voltage supplied by the 2 relays.

Circuit/System Description

There are 2 ignition voltage circuits supplied to the engine control module (ECM). One is supplied by the engine controls ignition relay, and the other is supplied by the ignition main relay. The ECM monitors and compares the ignition voltage supplied by the 2 relays.

 

P1682

• The engine controls ignition relay is commanded ON.
• Ignition voltage is greater than 5.5 V.
• The DTC runs continuously when the above conditions are met.

P1682

The ECM detects that the voltage level difference is greater than 3 V between the 2 ignition voltage circuits for greater than 1 s.

Circuit/System Testing

Note: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing unless sent here from Engine Cranks But Does Not Run.

1. Ignition OFF, disconnect the KR75 Engine Controls Ignition Relay.
2. Verify a test lamp illuminates between ground and the B+ terminals listed below:
   • Terminal 86
   • Terminal 30
    
   • If the test lamp does not illuminate
     Replace the front compartment fuse block.
    
   • If the test lamp illuminates
     Note:

     • High resistance in the circuit/underhood fuse block for either the KR75 Engine Controls Ignition Relay or the KR73 Ignition Main Relay can cause DTC P1682 to set.
     • A short to voltage on any of the circuits supplied by the engine controls ignition relay can cause DTC P0690 to set.
   
   
3. Ignition ON.
4. Verify that a test lamp does not illuminate between the ignition voltage circuit terminal 87 and ground.
   • If the test lamp illuminates
    
   1. Ignition OFF, disconnect the X1 harness connector at the K20 Engine Control Module.
   2. Ignition ON.
   3. Test for less than 1 V between ground and connector terminal 73.
      • If 1 V or greater, repair the short to voltage in the circuit.
      • If less than 1 V, replace the K20 Engine Control Module.
      
      
       
    
   • If the test lamp does not illuminate
   
   
5. Ignition OFF, connect a 20 A fused jumper wire between the B+ circuit terminal 30 and the ignition voltage circuit terminal 87.
6. Ignition ON.
7. Verify the scan tool Engine Controls Ignition Relay Feedback Signal parameter displays B+.
   • If B+ is not displayed
    
   1. Ignition OFF, disconnect the X1 harness connector at the K20 Engine Control Module
   2. Test for less than 2 Ω in the relay switch ignition voltage circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
       
      • If less than 2 Ω
      
      
   3. Test for infinite resistance between the relay switch ignition voltage circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the K20 Engine Control Module.
      
      
       
    
   • If B+ is displayed
   
   
8. Ignition OFF, connect a DMM, set to the diode setting, between control circuit terminal 85 and ground.
9. Verify the DMM displays OL.
   • If OL is not displayed
    
   1. Disconnect the X1 harness connector at the K20 Engine Control Module.
   2. Test for infinite resistance between ground and the relay control circuit.
      • If less than infinite resistance, repair the short to ground in the circuit.
      • If infinite resistance, replace the K20 Engine Control Module.
      
      
       
    
   • If OL is displayed
   
   
10. Ignition ON.
11. Verify the DMM displays less than 1 V.
    • If 1 V or greater
     
    1. Ignition OFF, disconnect the X1 connector at the K20 Engine Control Module.
    2. Ignition ON.
    3. Test for less than 1 V on the relay control circuit.
       • If 1 V or greater, repair the short to voltage on the circuit.
        
       • If less than 1 V
       
       
    4. Test for less than 2 Ω in the control circuit end to end.
       • If 2 Ω or greater, repair the open/high resistance in the circuit.
       • if less than 2 Ω, replace the K20 Engine Control Module.
       
       
        
     
    • If less than 1 V
    
    
12. Test or replace the KR75 Engine Controls Ignition Relay.

Component Testing

Relay Test

1. Ignition OFF, disconnect the KR75 Engine Controls Ignition Relay.
2. Test for 70–110 Ω between terminals 85 and 86:
   • If less than 70 Ω or greater than 110 Ω
     Replace the relay.
    
   • If between 70–110 Ω
   
   
3. Test for infinite resistance between the terminals listed below:
   • 30 and 86
   • 30 and 87
   • 30 and 85
   • 85 and 87
    
   • If less than infinite resistance
     Replace the relay.
    
   • If infinite resistance
   
   
4. Install a 20 A fused jumper wire between relay terminal 86 and 12 V. Install a jumper wire between relay terminal 85 and ground.
5. Test for less than 2 Ω between terminals 30 and 87.
   • If 2 Ω or greater
     Replace the relay.
    
   • If less than 2 Ω
   
   
6. All OK.

 

[asilverblazer]

I think the P1682 is the code you should focus on, my brief read of the information make me think one of the ignition relays is sticking.