Where is the starter relay on the ŠKODA Octavia A5: search, check and replacement

Owners ŠKODA Octavia A5 (body 1Z3, 2004–2013) sooner or later encounter problems starting the engine. One of the most common reasons is a malfunction starter relay or its circuits. But where exactly to look for this element in the fuse block? The answer is not as obvious as it seems: on different modifications Octavia A5 (including RS, Scout and versions with diesel engines) the location may differ.

In this article we will not only show exact location of the starter relay with photos and diagrams, but we’ll also look at:

• 🔍 Symptoms of a problem — how to distinguish a problem with the relay from a breakdown of the starter or battery itself.
• 🔧 Step by step instructions on checking the relay with a multimeter (even without experience).
• ⚠️ Common mistakes when replacing, which can damage the engine ECU.
• 📌 Differences in location for gasoline (1.4 TSI, 1.6 MPI, 1.8 TSI) and diesel (1.9 TDI, 2.0 TDI) versions.

We will pay special attention hidden relay in the block under the hood (K75) - it is often overlooked, attributing the fault to the starter. All data is confirmed by manuals ŠKODA and experience of service centers.

Where is the starter relay on the ŠKODA Octavia A5: diagrams and photos

On Octavia A5 The starter relay may be located in two places depending on the year of manufacture and configuration:

1. Main fuse box in the passenger compartment (to the left of the steering wheel, under the instrument panel). Here is main starter relay (denoted as J53 or K75 in the documentation).
2. Additional block under the hood (near the battery). In some versions, the relay is duplicated here or is starter interlock relay (immobilizer).

For a precise search, use the table below. Please note that on machines with DSG (robotic gearbox) diagram may vary!

Engine model	Year of issue	Relay location	Designation on the diagram
1.4 TSI, 1.6 MPI	2004–2008	Block in the cabin (under the steering wheel)	K75 (starter relay)
1.8 TSI, 2.0 TSI	2009–2013	Block under the hood + interior	J53 (main thing) + K75 (duplicate)
1.9 TDI, 2.0 TDI	All years	Block in the cabin (near the brake pedal)	K75 + fuse S10

📌 How to find a block in the cabin? Remove the cover under the steering wheel (unsnap 2 latches) - the starter relay is usually black with markings 87 or 30 on the body. The photo below shows a typical view of the block for Octavia A5 1.6 MPI:

Signs of a faulty starter relay: how to distinguish it from other breakdowns

Symptoms of a faulty relay are often confused with problems starter, battery or even immobilizer. Here are the key signs that the relay is to blame:

• 🔊 Starter clicking without turning — one loud click is heard when turning the key, but the engine does not start.
• 🔄 Intermittent failure — the starter works every other time (for example, it doesn’t work in the morning, but it’s normal in the afternoon).
• 💡 The warning lights go out when trying to start - indicates an open circuit in the relay.
• 🔋 There is voltage at the starter, but no signal (checked with a multimeter).

⚠️ Attention: If when you turn the key no clicking, the problem is rather fuse (check S10 in the cabin unit) or in lock-lock contact group.

To rule out other malfunctions, perform a quick diagnosis:

1. Check the voltage at battery (must be ≥) 12.4 V).
2. Make sure engine weight Not oxidized (clean contact on the body).
3. Try starting the engine. starter-on (closing the contacts on the relay).

How to test the starter relay without a multimeter?

If there is no tester, you can temporarily install a knowingly serviceable relay (for example, from a cooling fan - they are often interchangeable). If the starter works, the problem is the relay.

Step-by-step instructions: how to test the starter relay with a multimeter

The relay check takes 5-10 minutes and does not require the starter to be removed. You'll need:

• 🔧 Multimeter (or 12V control lamp).
• 🔌 Screwdriver to remove the lid of the fuse block.
• 📄 Relay pattern (see para. below).

Step 1. Removal of relay

Disable negative battery terminal (required!) Find the starter relay (see para. Then, remove it from the nest and pull it up.

Step 2. Check the winding

Connect the multimeter in mode 200 Ohm conclusion 85 and 86 (control contacts). Resistance must be within 50–120 Ohm. If cliff (∞) or short-circuit (0 ohms) - The relay is broken.

Step 3. Checking contacts

Connect the multimeter in mode diode continuity between 30 and 87. When submitting 12 V on 85 and 86 An audible signal should be heard (contacts closed). If not, the relay should be replaced.

💡 Tip: If the relay is working but the starter is not working, check it out. fuse S10 (10 A) In the cabin block, it is responsible for the control chain.

How to replace the starter relay on a ŠKODA Octavia A5: step by step with photos

Replacing the relay is a simple operation, but there are nuances that can lead to short circuit or eb. Follow the instructions:

Step 1. Preparation

• 🔌 Disable battery (First minus, then plus).
• 📸 Take a picture of the location of the relay and fuses – this will help avoid confusion during the reverse assembly.
• 🧤 Wear gloves – contacts in the block are often oxidized.

Step 2. Removing the old relay

Carefully pull the relay upwards, swaying from side to side. If it is "feeling," use a flat screwdriver, tucking it from the side. Don't try too hard - You can damage the nest!

Step 3. Installation of a new relay

Put a new relay in. until it clicks. Make sure it sits tight - even a small backlash can cause burning of contacts. For Octavia A5 fitting relays:

• 🔹 Original: VAG 1J0 951 253 (black, 12V).
• 🔹 Analogs: Bosch 0 332 019 150, Hella 4RA 003 507-331.

⚠️ Attention: After replacing the relay be sure to reset the ECU errors (if they were). To do this:

1. Turn on the ignition for 10 seconds (without starting the engine).
2. Turn the ignition off and on again.
3. Start the engine.

Common mistakes when replacing a starter relay and how to avoid them

Even experienced car owners make mistakes that lead to repeated breakdowns or expensive repairs. Here are the most common:

1. Ignoring oxidized contacts
   

   If the relay socket is dirty, the new relay will quickly fail. Clean your contacts alcohol solution or special liquid Kontakt 60.

2. Installing a relay from another model
   

   Relay from VW Golf 5 or Audi A3 may not be able to current characteristics. Use only the original or certified analogues.

3. Failure to check fuse S10
   

   If the fuse is out, the new relay will not work. Always check him out. visually and a multimeter.

4. They forget about the immobilizer
   

   On Octavia A5 with immobilizer of the third generation The starter relay is connected to the control unit. After the replacement, it is necessary key retraining.

🔧 How to avoid problems?

• 🔍 Before replacement ring the chain from relay to starter (wire usually) red with a black stripe.
• 📋 Lead replacement log Write down the date and article of the installed relay.
• 🚗 After replacement Check the starter 3-5 times This will reveal the hidden defects.

Differences in the location of the starter relay on petrol and diesel Octavia A5

On Octavia A5 with diesel engines (1.9 TDI, 2.0 TDI) the layout of the starter relay has features:

Engine type	Starter relay seat	Additional relays	fuse
Gasoline (1.4–2.0 TSI)	The cabin unit (K75)	Locking relays (J53) under the hood	S10 (10 A)
Diesel (1.9–2.0 TDI)	The cabin unit (K75) + engine compartment duplicate	Relays of glow plugs (J317)	S10 (10 A) + S18 (15 A)

🔍 Why are there two diesel relays?

On diesel Octavia A5 used starter-locking, immobilizer and Diesel Control Unit (EDC). If it fails, the starter may idle (no fuel supply)

📌 How to find a duplicate relay under the hood?

It is located in plastic-block next to the battery (cover with an inscription) K75 or SR). The photo below shows a typical view of the block for 2.0 TDI:

⚠️ Attention: On diesel versions it's impossible Check the starter relay by direct closing of contacts! It could put you in a position. injectors or injection pump.

FAQ: Frequently asked questions about the starter relay on the ŠKODA Octavia A5

Is it possible to drive with a faulty starter relay?

Technically yes, but this dangerous. If the relay "sticks" in a closed state, the starter will work constantly, which will lead to:

• 🔥 Starter overheating and its failure.
• 🔋 Low battery in 1–2 hours.
• ⚡ Fire risk due to a short circuit.

We recommend replacing the relay at first sign of failure.

Which Starter Relay is Right for the Octavia A5 1.6 MPI?

For Octavia A5 1.6 MPI (2004-2010) are suitable:

• 🔹 Original: VAG 1J0 951 253 (black, 12V).
• 🔹 Analogues: Bosch 0 332 019 150, Meat & Doria 95.12.8700.

💡 Important: Relay from Octavia A4 or Fabia Not suitable - different current load!

Why does the starter spin after the relay is replaced, but the car does not start?

Possible reasons:

1. Immobilizer faulty Check if the light bulb is flashing on the panel.
2. No signal from the knee-shaft sensor. (G28) - check the connector and the circuit.
3. Fuel injectors clogged (relevant for diesel engines).
4. ECU failure Try to reset the errors by turning off the battery for 10 minutes.

📌 Diagnostics: Connect a diagnostic scanner (for example, VCDS) and check for errors in engine block (01).

How to test the starter relay without a multimeter?

Method 1: Replacing with a known good one

Take the relays from cooling fan or low beam (They are often interchangeable). If the starter starts, your relay is malfunctioning.

Method 2: Direct closure of contacts
Be careful! Remove the relay and close the contacts 30 and 87 screwdriver. If the starter spins, the relay must be replaced. Do not use this method on diesel engines!

Where to buy the original starter relay for the Octavia A5?

Original relay VAG 1J0 951 253 you can buy:

• 🛒 Official ŠKODA dealers - 12 months warranty, but the price is ~1,500-2000 rubles.
• 🌍 Online stores: Exist.ru, Autodoc.ru, Emex.ru - price from 800 rubles.
• 🔧 Autoelectric stores: Bosch or Hella - analogues cost 500-900 rubles.

⚠️ Attention: When buying a used relay, check it out. winding resistance (must be 50–120 Ohm).