Error P1122 on Nissan Primera: a complete analysis of causes and solutions

Fault code P1122 on Nissan Primera (especially on models with engines QR25DE or SR20DE) is one of the most common problems that owners face. This error is related to the fuel control system and can manifest itself as unstable engine operation, increased fuel consumption, or even a transition to emergency mode. Unlike universal errors (e.g. P0300), P1122 specific to Nissan and requires a special approach to diagnosis.

In this article we will look in detail at what is hidden behind the code. P1122, which system components may fail, and how to fix the problem yourself - from simple checks to complex procedures. We will pay special attention non-obvious reasons that are often missed even by experienced craftsmen, for example, contamination of the throttle valve or malfunction of the absolute pressure sensor. If your Primera started to “go dumb”, twitch or show Check Engine - read on.

What does error code P1122 mean on Nissan Primera?

Code P1122 stands for «Throttle Position Sensor Circuit Low Input» — low signal of the throttle position sensor circuit (TPS). However, in the context Nissan Primera this error is often associated not only with the sensor itself, but also with the electronic throttle control system (Electronic Throttle Control, ETC). Unlike classic mistakes TPS (For example, P0120), P1122 may indicate:

• 🔧 Throttle Position Sensor Malfunction (wear, contamination or broken circuit).
• ⚡ Wiring problems between TPS And ECU (oxidation of contacts, short circuit).
• 🛠️ Throttle assembly contamination, leading to incorrect sensor readings.
• 🔄 Malfunctions of the electronic control unit (ECU) or incorrect throttle adaptations.

It is important to understand that P1122 - this is not a sentence, but a signal about the need for diagnosis. In 60% of cases, the problem is solved by cleaning the throttle or replacing the sensor, but sometimes flashing is required ECU or replacing the wiring harness. Next, we will look at how to accurately determine the culprit.

The main causes of P1122

To effectively resolve an error, you need to understand its root cause. Below is a list of the most likely culprits, ranked by frequency of occurrence on Nissan Primera:

1. Dirty throttle valve. Carbon deposits and oil deposits interfere with the normal movement of the damper, causing the sensor TPS produces incorrect signals. This is especially true for engines with mileage over 100 thousand km.
2. Faulty throttle position sensor. Over time, the resistive layer of the sensor wears out, which leads to “dips” in the signal.
3. Wiring problems. Oxidation of contacts in the connector TPS or a broken wire between the sensor and ECU.
4. Malfunctions ECU. It is rare, but it happens that the control unit incorrectly interprets signals due to software errors.
5. Accelerator pedal malfunction (for models with electronic pedal). The sensor in the pedal may produce incorrect data, which leads to a conflict with TPS.

Interesting fact: on Primera P12 (2002–2007) error P1122 often appears after replacing the battery or resetting ECU. This is due to the need throttle adaptationwhich many people miss. More details about this can be found in the troubleshooting section.

How to diagnose P1122: step-by-step instructions

Diagnosis of the error P1122 requires a systematic approach. Start with the simplest checks and gradually move on to more complex ones. You will need:

• 🔧 Multimeter (to check voltage and resistance).
• 🔍 Flashlight and magnifying glass (for inspecting wiring).
• 🧴 Throttle body cleaner (eg Liqui Moly Pro-Line).
• 💻 Diagnostic scanner (for example, ELM327 or Launch CReader).

Algorithm of actions:

1. Checking the throttle valve

Remove the air duct and inspect the damper. If black soot or oil deposits are visible on the walls, this is the first reason P1122. Clean the valve with a special product (do not use acetone or gasoline!). After cleaning, do throttle adaptation (instructions below).

2. TPS sensor diagnostics

Disconnect the sensor connector and check:

• 🔋 Supply voltage: between contacts 1 (+5V) and 2 (ground) there should be 4.8–5.2V.
• 📉 Sensor signal: between contacts 3 and 2 with the damper closed - 0.3–0.7V, when open - 3.5–4.5V.
• 🔄 Smoothness of signal change: When the damper opens slowly, the voltage should increase without surges.

If the signal “jumps” or is absent, the sensor is faulty. Replacement will cost 1 500–3 000 ₽ (original Nissan 22680-4M000).

3. Wiring check

Inspect the wiring harness from TPS to ECU on the subject:

• 🔥 Melted or rubbed areas.
• 💧 Traces of oxidation in the connectors (especially after washing).
• 🔌 Reliability of contacts (sometimes it’s enough just to reconnect the connector).

How to test wiring with a multimeter?

Set the multimeter to resistance test mode. Disconnect the TPS and ECU connectors. Test each wire for an open (resistance should be close to 0 ohms). Check that there is no short circuit between the wires (the resistance should be infinite).

How to resolve error P1122: from simple to complex

Depending on the cause, solutions P1122 range from basic to labor-intensive. Below is a checklist of solutions, sorted by effectiveness.

1. Cleaning the throttle body

The simplest and most effective method for 40% of cases. Use throttle body cleaner (not carbcleaner!). Algorithm:

1. Remove the air duct and open access to the damper.
2. Apply the cleaner to the walls and the damper itself, remove carbon deposits with a soft cloth.
3. Turn the valve manually so that the product penetrates into all grooves.
4. Repeat 2-3 times, then dry (do not use compressed air!).

After cleaning be sure to perform throttle adaptation (see next section).

2. Throttle adaptation

On Nissan Primera After any manipulations with the throttle, an adaptation reset is required. This can be done in two ways:

Method 1: Through a diagnostic scanner

Connect the scanner (for example, Launch X431) and select the function Throttle Valve Learning or ETC Reset. Follow the instructions on the screen.

Method 2: Manually (for models without a scanner)

1. Заглушите двигатель, включите зажигание на 3 секунды.
2. В течение 5 секунд 5 раз полностью нажмите и отпустите педаль газа.
3. Подождите 7 секунд, затем нажмите педаль газа до упора и удерживайте 10 секунд.
4. Отпустите педаль, выключите зажигание на 10 секунд.
5. Заведите двигатель и проверьте ошибки.

If adaptation does not help, proceed to replacing the sensor or checking ECU.

3. Replacing the TPS sensor

If the sensor is faulty, replacing it will take 15–20 minutes:

1. Disconnect the sensor connector.
2. Unscrew the two mounting bolts (usually a Phillips screwdriver).
3. Remove the old sensor and install a new one (original or equivalent Hitachi).
4. Connect the connector and perform adaptation.

Related errors and their meaning

Error P1122 rarely appears alone. It is often accompanied by other codes that help narrow down the search for the problem. Below is a table of the most common combinations:

Error code	Meaning	Probable Cause	Action
P0120	Throttle Position Sensor Circuit Malfunction	Break or short circuit in the wiring TPS	Check the wiring, replace the sensor
P0507	High idle speed	Throttle or air leak is dirty	Clean the throttle body, check the vacuum hoses
P2101	Throttle actuator malfunction	Problems with the throttle motor or ECU	Drive diagnostics, replacement of throttle assembly
P0100	Malfunction of the mass air flow sensor circuit (MAF)	Dirty or defective MAF	Clean or replace sensor

If together with P1122 present P0120 And P2101, with a 90% probability the problem is in the throttle assembly or its wiring. If added P0100 - check MAF, since it affects the calculation of the fuel mixture.

When is specialist help needed?

Not all cases of error P1122 you can decide on your own. Contact the service if:

• 🔧 After replacement TPS and adaptation error persists.
• ⚡ Diagnostics showed problems with ECU (for example, there is no power at the connector).
• 🔄 The engine is unstable even after resetting errors (there may be problems with the firmware).
• 💥 Additional errors have appeared related to the ignition or injection system (P0300–P0306).

The service will offer you:

• 🔍 Deep diagnostics ECU with firmware check.
• 🔧 Replacing the throttle assembly (if the motor or mechanical part is worn out).
• ⚡ Reflashing the control unit (relevant for models with “crooked” firmware).

⚠️ Attention: If after replacing the throttle assembly the error P1122 persists, the reason may be the incompatibility of the new node with the firmware ECU. In this case, the firmware needs to be adjusted or the unit replaced.

Preventing error P1122 on Nissan Primera

To avoid reappearance P1122, follow these guidelines:

• 🧴 Clean the throttle valve every 30,000–50,000 km (or more often if the engine “eats” oil).
• ⛽ Use quality fuel. Bad gasoline accelerates the formation of carbon deposits.
• 🔋 Monitor your battery status. Voltage sags can disrupt adaptations ECU.
• 🔌 Check your contacts connectors TPS And MAF at every maintenance.
• 📊 Reset adaptations after any work on the throttle or ECU.

If your Primera is operated in conditions of high humidity or frequent temperature changes, treat the sensor contacts contact lubricant (For example, CRC 2-26). This will prevent oxidation and short circuits.

FAQ: Frequently asked questions about P1122 on Nissan Primera

Is it possible to drive with error code P1122?

Short term - yes, but not recommended. Error P1122 may lead to:

• ⚠️ Unstable engine operation (dips, jerks).
• ⛽ Increased fuel consumption (up to +2–3 l/100 km).
• 🚗 Switching to emergency mode (limiting speed).

Long-term driving with this error accelerates wear of the catalyst and lambda probes.

How much does it cost to fix P1122 in the service?

The cost depends on the reason:

• 🧹 Cleaning the throttle: 1 000–2 000 ₽.
• 🔧 Replacing the sensor TPS: 3 000–5 000 ₽ (with work).
• 🔄 Throttle adaptation: 500–1 500 ₽.
• 🖥️ Diagnostics ECU: 2 000–4 000 ₽.

If you need to replace the throttle assembly, be prepared for 15 000–25 000 ₽.

Could P1122 be caused by bad gasoline?

Yes, but indirectly. Bad fuel leads to:

• 🔥 Accelerated formation of soot on the damper and intake valves.
• 🛢️ Sensor contamination MAF, which affects the calculation of the fuel mixture.

The error itself P1122 It does not occur due to gasoline, but it aggravates the problems leading to its occurrence.

How to reset error P1122 without a scanner?

You can reset the error by disconnecting the battery:

1. Disconnect the negative terminal of the battery for 10–15 minutes.
2. Reconnect and start the engine.
3. If the cause is eliminated, the error will not return.

⚠️ Attention: This method will reset all adaptations ECU, including idle settings. After connecting the battery, throttle adaptation may be required.

What TPS sensor analogues are suitable for Primera?

Besides the original (Nissan 22680-4M000), you can use:

• 🔹 Hitachi TPS003 (complete analogue, price ~2 000 ₽).
• 🔹 Blue Print ADT33501 (quality substitute).
• 🔹 Febi 22680 (budget option, ~1 500 ₽).

When choosing an analogue, be sure to check the catalog number with VIN your car.