Error P173A on <em>Nissan Juke</em>: a complete analysis of the causes and solutions

Nissan Juke is a popular crossover with a bright design, but even it is not immune to transmission problems. Error P173A - one of those that can take owners of models with a CVT by surprise JF015E or JF016E. This code indicates a malfunction in the transmission control system and cannot be ignored: the consequences can range from loss of dynamics to complete failure of the transmission.

Unlike engine errors, which often manifest themselves with obvious symptoms (tripping, smoke), P173A can remain unnoticed for a long time - until it reaches a critical stage. In this article we will look at what exactly this code means for Juke (including restyled versions 2014–2019), how to correctly diagnose it without an expensive scanner, and what steps will help fix the problem at minimal cost. We will pay special attention to typical repair mistakes that only aggravate the situation.

What does error P173A mean on Nissan Juke?

Code P173A stands for "Valve body pressure control solenoid circuit malfunction" (Pressure Control Solenoid "A" Circuit Malfunction). In CVTs Nissan This solenoid is responsible for regulating the oil pressure in the torque converter and friction clutches. If it doesn't work correctly:

• 🔧 The variator begins to “slip” when accelerating (especially noticeable at speeds of 40–60 km/h).
• ⚠️ The dashboard lights up Check Engine and/or transmission icon.
• 📉 Power drops, the car reacts poorly to the gas pedal.
• 🔄 The box goes into “emergency mode” (one gear is fixed, usually 3rd or 4th).

It is important to understand that P173A - this is not a condemnation of the variator, but a signal of a problem in electrical or hydraulic part. In 60% of cases, the solenoid itself is to blame (wear, clogging), in 30% - wiring or connectors, and only in 10% - mechanical damage to the box. However, if you ignore the error, the solenoid may fail completely, which will lead to a chain reaction of malfunctions.

⚠️ Attention: On Nissan Juke 2011–2013 model years error P173A often accompanied by code P0776 (clutch pressure solenoid malfunction). If you see both codes at the same time, the problem is almost certainly in the valve body and requires disassembly and cleaning.

Main causes of P173A

To effectively resolve an error, you need to understand its root cause. For Juke with variator JF015E/JF016E The following scenarios are typical:

Reason	Symptoms	Difficulty in eliminating
Solenoid clogged (wear products, metal shavings)	Smooth increase in symptoms, error appears after oil warms up	Medium (requires removal of the variator pan)
Open or short circuit in wiring	The error appears randomly and may disappear after restarting the engine.	Low (check with multimeter)
Malfunction of the control module (TCM)	Multiple transmission errors, the box is “buggy” even when cold	High (needs diagnostics at a service station)
Low level or old oil in the variator	The error appears after 100+ thousand km, accompanied by jerks	Low (oil change + filters)
Mechanical wear of the valve body	Permanent error, the box does not exit emergency mode	High (replacement of valve body)

Vehicles that are especially vulnerable to this error are:

• 🚗 Operated in city mode with frequent traffic jams (oil overheating).
• 🛣️ We traveled more than 150 thousand km without changing the oil in the variator.
• 🔧 Subjected to unqualified repairs (for example, after an accident).

How to diagnose P173A without a scanner?

If you do not have diagnostic equipment, you can conduct a preliminary check yourself. Here is a step-by-step algorithm:

1. Check the oil level in the variator.

   On Nissan Juke this is done through the inspection hole (not the dipstick!). The oil should be hot (drive 10–15 km) and drip in a thin stream with the plug open. The color of the oil should not be black or have a metallic sheen.

2. Inspect the solenoid connectors.

   The valve body is located under the variator pan. Disconnect the solenoid connector Pressure Control Solenoid A (usually the middle connector in the row) and check for oxidation or damage to the contacts.

3. Test the circuit with a multimeter.

   The resistance of a working solenoid should be within the range 10–20 Ohm. If the device shows OL (break) or 0 ohm (short circuit), solenoid is faulty.

4. Check the power supply.

   When the ignition is on, the solenoid connector should show 12 V between the positive wire and ground. No voltage indicates a problem in the wiring or control unit.

If all checks were successful, but the error remains, the problem may lie in TCM control unit or the mechanical part of the variator. In this case, you cannot do without in-depth diagnostics at a service station.

⚠️ Attention: On Nissan Juke 2015–2019 with variator JF016E error P173A sometimes occurs after updating the TCM firmware. If the code appears immediately after visiting the dealer, try resetting the box adaptations via a scanner (procedure CVT Relearn).

Step-by-step instructions for resolving the error

Depending on the cause, repair methods will vary. Below are proven solutions for Juke, from simple to complex.

1. Changing the variator oil and filters

If the oil is old or its level is critically low, first aid is a complete fluid change NS-3 (for CVTs Nissan) and filters (coarse and fine). For Juke will be required 7–8 liters of oil. Important:

• 🔧 Use only original liquid or analogues (Idemitsu CVT, Ravenol CVT).
• 🧹 Rinse the tray with magnets (remove metal shavings).
• 🔄 After replacement, perform the box adaptation procedure (via a scanner or the “learning” method: smoothly accelerate to 100 km/h 3 times and slow down).

2. Clean or replace the pressure solenoid

If the solenoid is clogged, you can try cleaning it. To do this:

1. Remove the variator pan and get to the valve body.
2. Remove the solenoid Pressure Control Solenoid A (usually it's marked as PCS-A on the body).
3. Wash it in clean gasoline or a special cleaner (WD-40 Specialist).
4. Check the mobility of the rod - it should move smoothly, without jamming.

If the solenoid is faulty (breakage, mechanical damage), it must be replaced. For Juke original parts fit 31726-3MX0A or analogues from ATP, Sonnax.

3. Repair of wiring or connectors

If the problem is electrical:

• 🔌 Clean the oxidized contacts on the solenoid connector (use contact lubricant after cleaning).
• 🔍 Check the circuit from the solenoid to the control unit for breaks (especially in places where the harness is bent near the box).
• 🛠️ If necessary, replace damaged wires using heat shrink tubing for insulation.

4. Replacing the valve body or variator

On Nissan Juke with a mileage of over 200 thousand km, error P173A may indicate wear of the valve body or the gearbox itself. In this case, partial repairs (replacement of solenoids) will give a temporary effect - replacement of the valve body assembly or the entire variator is required. The cost of a new hydraulic unit for JF015E - from 40,000 rubles, used variator - from 80,000 rubles.

Common repair mistakes and how to avoid them

Many owners Juke encounter a relapse of the error P173A after self-repair. Here are the most common mistakes:

1. Using non-original oil.

   Cheap analogues (for example, ATF instead of CVT Fluid) do not have the necessary friction properties, which accelerates the wear of the solenoids. Consequence: the error returns after 1–2 thousand km.

2. Incomplete rinsing of the pan.

   If you leave metal shavings on the magnets or in the valve body channels, they will quickly clog the solenoids. Always use flushing fluid for variators (For example, Liqui Moly CVT Spulung).

3. Ignoring box adaptation.

   After changing the oil or solenoids, the variator needs to be “trained” again. Without this, the control unit will not work optimally, and the error may return.

4. Buying used solenoids.

   Used solenoids often have hidden wear. Savings of 2–3 thousand rubles. may result in repeated repairs.

Cost of repairs at a service station vs. do-it-yourself repair

Elimination prices P173A vary depending on the cause and region. Below is a rough breakdown for Nissan Juke:

Type of repair	Cost (on your own)	Cost (STO)
Oil + filter change	3,000–5,000 rub. (oil + filters)	6,000–9,000 rub.
Cleaning the solenoid	0 rub. (if you have a tool)	2,000–4,000 rub.
Solenoid replacement	4,000–7,000 rub. (detail)	10,000–15,000 rub.
Replacing the valve body	40,000–60,000 rub. (detail)	70,000–100,000 rub.
Diagnostics (scanner + check)	—	1,500–3,000 rub.

Self-repair is beneficial if you have:

• 🔧 Experience with transmissions (variators Nissan sensitive to assembly errors).
• 🛠️ Special tool (torque wrench, pallet puller).
• 📋 Access to technical documentation (for example, manual Nissan Juke F15).

If at least one item is missing, it is better to contact a service station. Errors in assembling the variator can lead to its complete failure.

What happens if you ignore P173A?

Driving for a long time with this error leads to:

- Accelerated wear of the variator belt (replacing it costs 30,000–50,000 rubles).

- Damage to the planetary mechanism (repair - from 80,000 rubles).

- Complete failure of the gearbox (replacement of the variator - 150,000–200,000 rubles).

In critical cases, a faulty solenoid can block the oil supply, which will lead to the box jamming while driving.

Preventing error P173A on Nissan Juke

To avoid problems with the CVT, follow these recommendations:

• 🔄 Change oil every 60,000 km (or once every 4 years if the mileage is low). For Juke with variator JF016E the interval can be increased to 90,000 km, but only when using original oil NS-3.
• 🚗 Avoid aggressive driving (sharp starts, long slips). CVT Nissan does not like high loads.
• 🔧 Check the oil level regularly (especially if you notice smudges under the box).
• 📊 Follow the adaptations: if after changing the oil or battery the box starts to twitch, follow the procedure CVT Relearn.
• 🛑 Do not tow a trailer or another vehicle — variator Juke not designed for high loads.

If your Juke often used in traffic jams or in hot climates, install additional variator cooling radiator. This will reduce the risk of oil overheating and extend the life of the solenoids.

FAQ: Frequently asked questions about error P173A

Is it possible to drive with error P173A if the car is still moving?

Short-term (1-2 days) - yes, but only if the box does not go into emergency mode. Driving for a long time with this error leads to accelerated wear of the variator belt and solenoids. If the error appears regularly, it is better to immediately start diagnosing it.

I reset the error with the scanner, but it returned after 100 km. What's the matter?

This is a typical sign dirty solenoid or wiring problems. If resetting does not help, you need to:

1. Ring the solenoid circuit.
2. Check the oil for metal shavings.
3. If necessary, clean or replace the solenoid.

How difficult is it to replace the solenoid yourself?

For an experienced car enthusiast, this is a task of medium difficulty. You will need:

• Remove the variator pan (you need a puller and sealant for installation).
• Disconnect the valve body connectors (carefully so as not to break the latches!).
• Remove and replace the solenoid (it is important not to mix them up!).

Without experience, it is better not to take risks - errors during assembly can damage the box.

What kind of oil to pour into the variator Nissan Juke 2015?

For CVTs JF016E (installed on Juke since 2014) must be used only NS-3 or its full analogues:

• Nissan CVT Fluid NS-3 (original, article KLE52-00004).
• Idemitsu CVT Type NS-3.
• Ravenol CVT NS-3.

Usage NS-2 or universal ATF-liquids are not allowed!

Can P173A be caused by bad gasoline?

No, directly - no. However, low-quality fuel can cause engine detonation, which transmits shock loads to the variator. In the long term, this accelerates wear on the solenoids. If the error appears after refueling at a questionable gas station, also check knock sensor And ignition coils.