Transmission 4-Wheel Drive High Indicator Open Circuit
P1805 — Transmission 4-Wheel Drive High Indicator Open Circuit
System: Powertrain | Type: Manufacturer-Specific | Make: Generic
P1805 is a manufacturer-specific powertrain diagnostic trouble code. It belongs to the P-prefix family of codes, which covers engine, transmission, emissions, or fuel-system faults.
When P1805 is stored, the module has detected an open (broken or disconnected) electrical path in the monitored circuit; and a signal or supply voltage higher than the expected operating range.
Scanning & clearing: A generic OBD-II scan tool will usually read and clear powertrain (P) codes. For live data, freeze-frame capture, and bi-directional tests you may need a more capable scan tool that supports the vehicle's ECM protocol.
P1805 is a manufacturer-specific code. The same code string on a different make may have a different meaning. Always confirm the code's definition against the vehicle's service information for the specific make and model under test.
The powertrain control module (PCM) or transfer case control module (TCCM) sets P1805 when it detects an open circuit in the 4WD High indicator circuit. This circuit is responsible for illuminating the 4WD High indicator when the vehicle is engaged in 4WD High mode. An open circuit means there is a break in the wiring, preventing the signal from reaching the indicator.
Detailed possible causes for P1805 are available to TaT members.
Unlock with Free TrialStep-by-step diagnostic guidance for P1805 is available to TaT members. Our Diagnostic Assistant provides professional-level troubleshooting procedures written by experienced technicians.
Unlock with Free Trial| Code | P1805 |
| System | Powertrain |
| Type | Manufacturer-Specific |
| Make | Generic |
| Causes | Available |
| Diag. Assistant | Available |
| Video | — |
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