Faulty or misadjusted kick-down switch (at the pedal or throttle linkage, depending on model); Open circuit, chafed wiring or poor connection in the switch signal or ground wire; Corroded, loose or damaged connector at the switch or control module; Accelerator pedal or throttle linkage fault, or incorrect pedal travel, so the switch never closes; Blown fuse or loss of supply to the switch circuit; Faulty powertrain control module or transmission control module input.

P1836

Kick-Down Switch Failed Open.

Buick
Powertrain
Manufacturer code
Low severity

How this code is built

P: SystemPowertrain
1: Defined byThe manufacturer
8: AreaTransmission
36: FaultThe specific fault in that area

What it means

P1836 on a Buick means the powertrain control module has detected that the kick-down switch is reading open (failed open). This switch tells the transmission control logic when the throttle pedal has been pushed fully down for a forced downshift. The module set the code because the switch signal was missing or did not change when it should have, for example at wide-open throttle.

Symptoms

Malfunction indicator lamp on
No kick-down or delayed downshift when the throttle is pressed fully
Transmission holding a higher gear under heavy acceleration
Poor overtaking performance
Harsh, late or unexpected shift behaviour
Transmission possibly defaulting to a limp or fixed shift strategy

Possible causes

Faulty or misadjusted kick-down switch (at the pedal or throttle linkage, depending on model)likely
Open circuit, chafed wiring or poor connection in the switch signal or ground wirelikely
Corroded, loose or damaged connector at the switch or control modulepossible
Accelerator pedal or throttle linkage fault, or incorrect pedal travel, so the switch never closespossible
Blown fuse or loss of supply to the switch circuitpossible
Faulty powertrain control module or transmission control module inputrare

How to diagnose

Read all stored and pending codes and freeze frame data, and note any other transmission or throttle codes
Check the live data for the kick-down switch state while pressing the pedal slowly to the floor, and see whether it changes
Inspect the switch, its mounting and the pedal or linkage for damage, wear or incorrect adjustment
Check the wiring and connectors from the switch to the control module for chafing, corrosion, water ingress and pin tension
Check the relevant fuse and the supply and ground at the switch against the wiring diagram for your model
Measure switch continuity with the pedal released and fully pressed, and compare with the specification
Test the signal wire for open circuit or short between the switch and module
If all wiring and the switch prove good, consider a control module fault and check for any applicable software updates for your model

How to fix

Replace or correctly adjust the kick-down switch and set the pedal or linkage travel to specification
Repair or replace damaged wiring and fix any open circuit in the signal or ground wire
Clean, repair or replace corroded or loose connectors
Replace the blown fuse after finding out why it failed
Repair or replace the accelerator pedal or linkage if it prevents full travel
Replace or reprogram the control module only after the rest of the circuit is proven good

Can I keep driving?

Low severity

The car can normally be driven as the main effect is a lost or delayed kick-down. Avoid relying on forced downshifts for overtaking and book it in soon, especially if the gearbox is shifting harshly.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.