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

The distributor pickup coil generates the G2 signal. That signal, plus the one from the CKP sensor, lets the fuel injection computer handle ignition timing and turn on the igniter, ignition coil, and fuel injectors.

Eventually, the distributor pickup coil's will fail. When that happens, the ignition system isn't gonna generate the spark the engine needs to start.

In this tutorial, I'll show you two quick tests you can perform on the pickup coil's to find out if it's still working or if it's toast.

APPLIES TO: This tutorial applies to the following vehicles:

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

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 CKP Sensor (1995-1997 1.8L Toyota Corolla).

Ignition System Wiring Diagram:

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

Engine No-Start Basics:

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

What Does The Distributor Pickup Coil Do?

To wrap our heads around the pickup coil's role in the ignition system, here's a brief breakdown of how it works:

• What it does: In the 1995-1997 1.8L Corolla, the distributor's pickup coil has one magnetic sensor that creates the G2 signal. This AC Volts signal is used to manage ignition spark and timing.
• About the G2 signal: It tells the fuel injection computer when a cylinder's hitting top dead center (TDC), so the computer can time the spark just right.
• How it works: When the engine's cranking or running, a toothed reluctor wheel spins past the magnetic sensor inside the distributor. That movement creates the AC voltage signal.
• Why it matters: The computer watches the G2 signal to know exactly when to trigger the ignition coil through the igniter. The coil fires off a high-voltage spark, which passes through the distributor cap, rotor, and wires to reach the right spark plug.

Symptoms Of A Bad Pickup Coil

If the pickup coil's shot, your engine might have trouble starting or could just shut off while you're driving. The two biggest symptoms of a bad pickup coil are:

1. Engine won't start:
   • The igniter never gets its IGT signal to turn on.
   • The ignition coil doesn't fire since the igniter never tells it to.
   • The fuel injection computer skips activating the fuel injectors.
   • The fuel pump stays off because the computer doesn't send the signal to start it.
2. Rough idling or random stalling:
   • The engine might misfire, run all shaky, or suddenly die while you're on the road.
3. Ignition system diagnostic trouble code (DTC):
   • 1995 OBD I - Code 12: G and NE Signal Problem.
   • 1996-1997 OBD II - P0340: Camshaft Position (CMP) Sensor Circuit Problem.

Distributor Connector Circuit Descriptions

Your 1995-1997 1.8L Toyota Corolla's distributor has a 4-wire connector. The connector coming out of the distributor itself has male spade terminals. The engine wiring harness connector has female terminals.

NOTE: The wire colors in the tables below match the engine wiring harness connectors, not the ones directly on the distributor.

1995 1.8L Corolla
Pin	Wire Color	Description
1	White (WHT)	NE- → Sensor Ground For G2
2	Black (BLK)	G2 → Camshaft Position Signal
3	Black with orange stripe (BLK/ORG)	B+ → Ignition 12 Volts
4	Black (BLK)	+B2 → Ignition Coil Activation Signal

1996-1997 1.8L Corolla
Pin	Wire Color	Description
1	White (WHT)	NE- → Sensor Ground For G2
2	Black (BLK)	G2 → Camshaft Position Signal
3	Black (BLK)	B+ → Ignition 12 Volts
4	Black (BLK)	+B2 → Ignition Coil Activation Signal

Where To Buy The Distributor Pickup Coil

The pickup coil isn't sold separately from the distributor, so if your test results indicate it's bad, you'll need to buy the entire distributor.

NOTE: Not sure if the distributor fits your particular Corolla? Don't worry. Once you get to the site, they'll ask you for the specifics of your vehicle. If it doesn't fit, they'll find you the right one.

TEST 1: Checking The Pickup Coil's Resistance With A Multimeter

The most common type of pickup coil failure is that it has suffered an internal short-circuit or open-circuit problem.

To check if the G2 sensor's got an internal electrical issue, we'll measure its internal resistance with a multimeter in Ohms mode.

Your multimeter should show:

• G2 Sensor: Between 185 and 265 Ohms when the engine's cold.

NOTE: Do the resistance test on the 4-wire connector that comes out of the distributor itself —the one with the male spade terminals.

Alright, here's how to do it:

1. 1

   Unplug the distributor's 4-wire connector.

2. 2

   Switch your multimeter to Ohms.

3. 3

   Probe terminals 1 and 2 of the distributor 4-wire connector.
   
   Those two terminals connect to the G2 sensor.

4. 4

   You should get a reading between 185 and 265 Ohms.

Now let's see what your results mean:

CASE 1: The G2 sensor's resistance is within the indicated range. That means the pickup coil doesn't have an internal electrical fault.

You don't have to, but if you wanna double-check the sensor is actually putting out a signal, go ahead and do TEST 2: TEST 2: Testing The Pickup Coil's Output With A Multimeter.

CASE 2: The G2 sensor's resistance is out of range. That confirms it's bad and needs to be replaced.

Since you can't just buy the pickup coil by itself, you're gonna have to swap out the whole distributor.

Still unsure? Run TEST 2 to be sure: TEST 2: Testing The Pickup Coil's Output With A Multimeter.

TEST 2: Testing The Pickup Coil's Output With A Multimeter

When you crank the engine, the G2 sensor puts out an AC voltage. You can easily check that with a multimeter set to Volts AC.

Here's what you wanna see:

• Good G2 sensor: While the engine's cranking, the multimeter should show between 0.4 and 1.2 Volts AC.
• Bad G2 sensor: If it's dead, the multimeter will stay at 0 Volts AC while cranking the engine.

NOTE: The G2 sensor's AC output depends on how fast the engine turns. That cranking speed heavily depends on your battery's charge. So if the battery's weak, you might not get an accurate reading. Make sure it's fully charged before doing this test.

Let's jump into the steps:

1. 1

   Unplug the distributor's 4-wire connector.

2. 2

   Set your multimeter to Volts AC.

3. 3

   Touch the test leads to terminals 1 and 2 on the distributor's 4-wire connector.
   
   Those two terminals correspond to the G2 sensor.
   
   NOTE: Be sure you're testing the male spade terminals on the distributor, not the female ones on the engine side.

4. 4

   Have someone crank the engine while you keep an eye on the multimeter.
   
   CAUTION: Be careful! Keep your hands clear of any moving parts while the engine is cranking.

5. 5

   You should see a voltage output between 0.4 and 1.2 Volts AC.

Here's how to read the results:

CASE 1: You're getting the expected AC voltage. That tells you the G2 sensor's doing its job.

If the engine is still not starting due to a lack of spark, your next step is to test the CKP sensor:

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

CASE 2: You see 0 Volts AC. That confirms the pickup coil's bad and the distributor needs to be replaced.

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 there:

• How To Test The Fuel Pump (1993-1997 1.8L Toyota Corolla).
• How To Test The MAP Sensor (1993-1997 1.8L Toyota Corolla).
• How To Test The Intake Air Temp (IAT) Sensor (1993-1997 1.8L Toyota Corolla).
• How To Test The Throttle Position Sensor (1993-1997 1.8L Toyota Corolla).