System: Powertrain (P-Code)
SAE Standard (Generic)
Family: Traction Control Input Signal Circuit
Code P0859: Traction Control Input Signal High
Diagnostic & Technical Explanation
Code P0859 (Traction Control Input Signal High) sets when the ECM/TCM sees an open, shorted, or implausible signal on the traction-control-system input line used to request torque reduction or shift adjustments during wheel slip. Causes are a network wiring fault between the ABS/traction module and ECM/TCM, a corroded connector, or an internal fault in the requesting module.
First-listed procedure
Rank #1
Inspect traction control network wiring/connectors
Easy DIY
This is the first procedure in the authored
consideration order, not a measured cause likelihood. Execute it only when its prerequisites
and diagnostic findings support it. Its cost and labor estimates (where known), the step-by-step procedure and the
remaining 2 procedure(s) are in the licensed dataset. Ordering context.
Full family: Traction Control Input Signal Circuit
What this page does not show
This page publishes the fault mechanism and the code index. The licensed dataset adds, for
every one of the 15,886 codes, the full authored repair set (56,729 procedures in total)
with the fields deliberately withheld here:
- Procedures 2..n after the first-listed procedure
- Aftermarket parts cost ranges in USD (
est_parts_cost_min/max_usd)
- Professional labor-hour estimates (
est_labor_hours)
- Step-by-step diagnostic and repair instructions
- Replacement-part mappings and catalog lookups
- 6,637 manufacturer-specific OEM codes across 32 makes ($149 tier)