How To Test The CKP Sensor (1995-1997 1.8L Toyota Corolla)

The crankshaft position (CKP) sensor on your 1995-1997 1.8L (7A-FE) Toyota Corolla can quickly and easily be tested with a multimeter.

In this tutorial, I'll show you two multimeter tests you can do on the CKP sensor to find out if it's good or bad.

This tutorial applies to the following vehicles:

• 1.8L (7A-FE) Toyota Corolla: 1995, 1996, 1997.
• 1.8L (7A-FE) Geo Prizm: 1995, 1996, 1997.

Ignition System Wiring Diagram:

• Ignition System Wiring Diagram (1995 1.8L Toyota Corolla).
• Ignition System Wiring Diagram (1996-1997 1.8L Toyota Corolla).

Ignition System Diagnostic Tests:

• How To Test The Ignition Coil (1995-1997 1.8L Toyota Corolla).
• How To Test The Igniter (1995-1997 1.8L Toyota Corolla).
• How To Test The Distributor Pickup Coil (1995-1997 1.8L Toyota Corolla).

Engine No-Start Basics:

• How To Troubleshoot An Engine No-Start Problem (1993-1997 1.8L Toyota Corolla).

Symptoms Of A Bad CKP Sensor

The CKP sensor usually fails in one of two ways —it either dies completely or acts up on and off (intermittent failure).

If it totally quits, your Corolla's not gonna start at all, until you replace the CKP sensor.

If it fails intermittently, the engine mostly runs fine, but sometimes it just refuses to start or may stall without notice.

When the crankshaft position sensor goes bad, the fuel injection computer usually throws a CKP sensor diagnostic trouble code (DTC):

• 1995 OBD I:
  • Code 12: G and NE Signal Problem.
  • Code 13: NE Signal Circuit Problem.

• 1996-1997 OBD II:
  • P0335: Crankshaft Position (CKP) Sensor Circuit Failure.
  • P1335: Crankshaft Position (CKP) Sensor Circuit Failure With The Engine Running.

Where To Buy A CKP Sensor And Save

The crankshaft position (CKP) sensor is a key component of the ignition system and plays a big part in keeping the engine running. Here are my recommendations:

TEST 1: Checking CKP Sensor Resistance With A Multimeter

The CKP sensor is a basic 2-wire magnetic pulse generator. You can test it in two ways:

• Measure its internal resistance with a multimeter in Ohms mode.
• Check its signal output with your multimeter set to Volts AC mode.

In this test section, we're gonna test the CKP sensor's internal resistance to see if it's in the right range or not.

Here's the resistance you should get:

• 1,630 to 2,740 Ohms when the engine's cold.
• 2,065 to 3,225 Ohms when it's warmed up.

Alright, let's jump in:

1. 1

   Disconnect the CKP sensor from its 2-wire connector.
   
   CKP Sensor Location: The CKP sensor's connector sits on the intake manifold's right side, close to injector #1.

2. 2

   Switch your multimeter to Ohms (Ω) mode.

3. 3

   Touch the multimeter leads to the male spade terminals on the sensor.
   
   IMPORTANT: Make sure you're testing the male terminals on the sensor itself —not the female ones of its 2-wire connector.

4. 4

   You should see an Ohms reading of:
   
   1.) 1,630 to 2,740 Ohms if the engine's cold.
   
   2.) 2,065 to 3,225 Ohms if it's hot.

Here's how to read your results:

CASE 1: The CKP sensor's resistance is within range. That means the sensor's doing its job.

You don't have to, but if you wanna double-check, you can go ahead and run TEST 2. Go to: TEST 2: Testing The CKP Sensor's Output With A Multimeter.

CASE 2: The CKP sensor's resistance is outside the expected range. That tells us the sensor's bad and you'll need to swap it out with a new one.

Again, not required —but if you wanna be extra sure, you can do TEST 2. Head to: TEST 2: Testing The CKP Sensor's Output With A Multimeter.

TEST 2: Testing The CKP Sensor's Output With A Multimeter

This last test checks the CKP sensor's signal output while the engine is cranking using a multimeter set to Volts AC mode.

While you crank the engine, the sensor should put out between 0.4 and 1.2 Volts AC.

If the sensor's toast, the multimeter's gonna read 0 AC Volts during the time the engine is cranking.

IMPORTANT: This test depends on how charged your Corolla's battery is. This is because the engine cranking speed, and thus the strength of the CKP sensor's signal depends on a fully charged battery. So, if your Corolla's battery is low or dead, charge it up fully before starting.

Here's how to do it:

1. 1

   Disconnect the CKP sensor from its connector.
   
   CKP Sensor Location: The connector's on the intake manifold's right side, close to injector #1.

2. 2

   Switch your multimeter to Volts AC mode.

3. 3

   Touch the multimeter leads to the CKP sensor's male spade terminals.
   
   NOTE: Make sure you're testing the male terminals on the sensor itself —not the female ones of its 2-wire connector.

4. 4

   Have someone crank the engine while you observe the multimeter.
   
   WATCH OUT: Be careful while the engine's turning over.

5. 5

   You should see the voltage bounce between 0.4 and 1.2 Volts AC as the engine cranks.

Here's how to read the results:

CASE 1: You saw the right AC voltage range on the multimeter. That means the CKP sensor's doing its job.

If the engine is not starting due to a lack of spark and you haven't tested the distributor pickup coil yet, do that now:

• How To Test The Distributor Pickup Coil (1995-1997 1.8L Toyota Corolla).

CASE 2: The multimeter showed 0 Volts AC. That means the crankshaft position sensor's bad and needs replacing.

More 1.8L Toyota Corolla Tutorials

You can find a complete list of 1.8L Toyota Corolla tutorials and wiring diagrams in this index:

• 1.8L Toyota Corolla Index Of Articles.

Here's a sample of the tutorials you'll find in the index:

• How To Test The Throttle Position Sensor (1993-1997 1.8L Toyota Corolla).
• How To Diagnose A Broken Timing Belt (1993-1997 1.6L Toyota Corolla).
• How To Test The Fuel Pump (1993-1997 1.8L Toyota Corolla).
• How To Test The Fuel Injectors (1993-1997 1.8L Toyota Corolla).