Ignition Relay Diagnosis. Chevrolet Corvette 1997

For 1990-2009 cars only

Makes 🢒 Chevrolet 🢒 1997 🢒 Corvette 🢒 Engine 🢒 Engine Controls - 5.7L 🢒 Ignition Relay Diagnosis

Engine Controls Components
Cell 20: Power, Ground, DLC and MIL
OBD II Symbol Description Notice

Circuit Description

The IGN relay protects the battery from a parasitic draw. The following components are powered by the IGN relay:

•	Injectors/Ignition coils

•	Throttle Actuator Control (TAC) module

•	Transmission

•	A/C system

•	EVAP solenoid

•	MAF sensor

•	AIR pump and AIR solenoid relays

•	TCC/Cruise and Extended Travel brake switches

Diagnostic Aids

Ignition (IGN) Relay Underhood Electrical Center Terminal Identification
Front of Vehicle
Left Side of Vehicle	Ignition	B+	Right Side of Vehicle
Left Side of Vehicle	Load	Ground	Right Side of Vehicle

•	The following may cause an intermittent:

-	Poor connections. Check for adequate terminal tension. Refer to Troubleshooting Procedures, Checking Terminal Contact (Body and Accessories/Wiring Systems) for proper procedure.

Corrosion

-	Mis-routed harness.

-	Rubbed through wire insulation.

-	Broken wire inside the insulation.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

For any test that requires probing the PCM or a component harness connector, use the Connector Test Adapter Kit J 35616 . Using this kit prevents damage to the harness connector terminals.

This step isolates the circuit from the IGN relay . All of the circuits at the relay are good if the test lamp illuminates.

The open circuit will be between the splice and the IGN relay.

Remove the underhood electrical center and inspect the circuits that are supplied a voltage by the IGN relay.

Step

Action

Value(s)

Yes

Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

Turn OFF the ignition.
Remove the underhood electrical center cover.
Remove the IGN relay.
Probe the B+ feed circuit to the IGN relay harness terminal with a test lamp J 35616-200 connected to a ground. Refer to Diagnostic Aids for the IGN relay terminal identification.

Does the test lamp illuminate?

Go to Step 3

Go to Step 8

Turn ON the ignition leaving the engine OFF.
Probe the ignition feed circuit to the IGN relay harness terminal with a test lamp J 35616-200 connected to a ground. Refer to Diagnostic Aids for the IGN relay terminal identification.

Does the test lamp illuminate?

Go to Step 4

Go to Step 9

Turn OFF the ignition.
Check the resistance of the IGN relay harness terminal ground circuit using a DMM J 39200 connected to the battery ground. Refer to Diagnostic Aids for the IGN relay terminal identification.

Is the resistance less than the specified value?

0-5ohms

Go to Step 5

Go to Step 10

Turn OFF the ignition.
Jumper the IGN relay B+ feed circuit and the IGN relay load circuit together using a fused jumper wire. Refer to Diagnostic Aids for the IGN relay terminal identification.
Probe the fuses for the following components with a test lamp J 35616-200 connected to a ground.

•

AIR PUMP

•

A/C

•

INJR1

•

INJR2

•	THROT CONT

•

ENG IGN

Does the test lamp illuminate?

Go to Step 6

Go to Step 11

Check for poor terminal contact at the IGN relay harness connector. Refer to Body and Accessories/Wiring Systems.

Did you find and correct the condition?

System OK

Go to Step 7

Replace the IGN relay.

Is the action complete?

System OK

Repair the open B+ supply to the IGN relay. Refer to Body and Accessories/Wiring Systems.

Is the action complete?

System OK

Repair the ignition feed circuit to the IGN relay. Refer to Body and Accessories/Wiring Systems.

Is the action complete?

System OK

Repair the open ground circuit for the IGN relay Refer to Body and Accessories/Wiring Systems. .

Is the action complete?

System OK

Repair the IGN relay load circuit. Refer to Body and Accessories/Wiring Systems.

Is the action complete?

System OK