System: Powertrain (P-Code)
SAE Standard (Generic)
Family: NH3 Sensor Heater Circuit
Code P24E7: NH3 Sensor Heater Circuit Low
Diagnostic & Technical Explanation
Code P24E7 (NH3 Sensor Heater Circuit Low) sets when the ECM detects an open circuit, out-of-range current, or a heater-performance fault while driving the heater that brings the NH3 sensor's ceramic element to operating temperature. Because the heater is sealed inside the sensor body, a genuine heater failure requires a complete sensor replacement, but the heater fuse and connector should be checked first since they are far less expensive to repair.
First-listed procedure
Rank #1
Replace blown NH3 heater fuse
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: NH3 Sensor Heater 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)