📌 Meaning of Code P1124
The code P1124 on a Nissan vehicle indicates that the throttle control motor relay (also called Throttle Control Motor Relay) is stuck (remained in open or closed position). This prevents the ECM (Engine Control Module) from properly controlling the throttle opening in an electronic throttle control system (ETC, Electronic Throttle Control).
In short, the ECM loses control of the throttle motor, which can cause abnormal engine behavior or activation of limp mode.
⚠️ Possible Symptoms
-
✅ Check Engine Light (MIL) on
-
🚫 Slow or impossible acceleration
-
⚠️ Safety mode activated (limited speed)
-
🛠️ Unstable idle
-
🚨 Abnormal accelerator pedal response
🛠️ Possible Causes
-
Faulty throttle control motor relay – Main component often responsible.
-
Open or shorted wiring – Cut, rubbed, or melted cables between the relay and ECM.
-
Poor or corroded electrical connection – Loose or oxidized connectors.
-
ECM problem (rare) – If the relay is good but remains inactive/uncontrolled, the ECM might be faulty.
✅ How to Fix Nissan Code P1124
🔧 Step 1: Visual Inspection
-
Locate the throttle control motor relay (often in the engine relay/fuse box).
-
Check the associated wiring and connectors:
-
No broken, melted, or exposed wires.
-
Connector pins clean, not bent, not corroded.
-
🔄 Step 2: Relay Test
-
Temporarily replace the relay with an identical one (same reference) to see if the problem disappears.
-
Or test the relay with a multimeter:
-
Check continuity between the control terminals (coil).
-
Apply 12V to the control terminals to see if the relay “clicks” (closes).
-
⚡ Step 3: Check Power Supply
-
Ignition ON, check if the relay output terminal provides 12V to the ECM.
-
If the relay works mechanically but is not controlled, suspect an ECM or ignition sensor fault.
🧪 Step 4: Code Clearing
-
Clear the P1124 code with an OBD-II diagnostic tool.
-
Restart the engine and test acceleration.
-
If the code returns, check the relay or wiring in depth.
💡 Tip
This code can make the vehicle unusable or very limited for driving. It is important to act quickly. The relay is inexpensive and is the first part to replace if no visible anomaly is found in the wiring.