Code
P1565
MERCURY
P — Powertrain
Speed Control Command Switch Out of Range High
Views:
UK: 36
EN: 41
RU: 34
AI status
Completed
Completed
100%
Causes
- Faulty speed control/cruise command switch (steering wheel switch)
- Short to battery voltage (VB) in the switch harness or connector
- Poor or corroded connector/terminal at the switch or PCM
- Damaged wiring (chafing, pinched, or exposed conductor) in the switch circuit
- Poor ground or supply reference to the switch circuit
- Faulty PCM or steering column control module (rare)
Symptoms
- Cruise control will not set or engage
- Cruise may disconnect immediately or not respond to set/resume commands
- Cruise control indicator may flash or remain off
- Possible intermittent operation of steering wheel switches
- Related stored codes for vehicle speed or voltage may also be present
What to check
- Retrieve freeze frame and stored data with a scan tool; note conditions when code set
- Check for other related DTCs (vehicle speed sensor, system voltage, steering wheel module)
- Visually inspect cruise switch/steering wheel controls, connectors, and wiring for damage or corrosion
- Backprobe the switch connector and monitor reference and signal voltages with ignition ON (engine off)
- Wiggle test the wiring and clock spring while watching live data for signal jumps
- Check connector pins for bent or pushed-out terminals and secure mating
Signal parameters
- Typical reference/supply voltage to switch: ~5 V (varies by system)
- Expected switch signal range: 0–5 V (steady values or momentary changes when buttons pressed)
- Out-of-range high condition: signal persistently near battery voltage (e.g., >4.5–5.0 V) or above expected threshold
- Open or short-to-ground would show very low/zero volts; short-to-VB shows near battery voltage (~12 V) when ignition ON (indicates wiring fault)
Diagnostic algorithm
- Scan for codes and note freeze-frame/live-data. Clear codes and attempt to reproduce to confirm repeatability.
- Inspect the steering wheel/cruise switch, connector, and wiring harness for damage, corrosion, or water intrusion. Repair any visible faults.
- Backprobe the switch connector: verify reference voltage, ground, and the switch signal circuit. Compare readings to expected values (see signal_params).
- Operate each cruise switch function while monitoring the signal. Look for correct voltage changes or persistent high values.
- Perform a wiggle test on the steering column wiring and clock spring while watching the live signal to find intermittent faults.
- Disconnect the cruise switch assembly and check if the code clears or a different code appears. If disconnecting clears the high signal, suspect the switch or harness.
- If wiring and switch test OK, inspect and test the clock spring (contact reel) for internal damage or short. Replace if necessary.
- If all wiring, switch, and clock spring confirm good, consider testing or replacing the PCM/steering module as a last step or consult manufacturer service data for module bench tests.
- After repairs, clear codes and road-test to verify the fault does not return and cruise functions correctly.
Likely causes
- Shorted wire to constant battery voltage at the cruise switch connector
- Internal switch failure causing a high-voltage output
- Corroded connector or poor contact raising the measured voltage
- Damaged clock spring causing intermittent high signal to PCM
Fault status
Status
P1565 — Speed Control Command Switch Out of Range High. PCM detected a switch/signal voltage or level above the expected range on the cruise control command circuit. This can prevent normal cruise control operation.
Repair difficulty: Medium
Diagnostic time: 0.5-2 hours
Similar codes
Your experience will help others
+100 karma for a short comment :)
Was this AI description helpful?
Your feedback helps improve AI descriptions.
👍 Like
0
👎 Dislike
0
Send to email