2.2/2.5L EFI Diagnostic Test Procedures

TEST 7 STEP D Checking the ignition coil primary windings for a short.



TEST 7 STEP E Checking the ignition primary circuit for a short to ground.



TEST 8 STEP A Checking for fault code 43.



TEST 8 STEP B Checking spark control wire between logic and [1][2]power modules for open.



TEST 15 STEP F Check for no 5 volt in system power circuit caused by shorted MAP sensor.



TEST 15 STEP G Check for no 8 volt in system power circuit caused by a shorted distributor pickup.



TEST 15 STEP H Checking system power circuit for 8 volt output from the [1][2]power module.



TEST 15 STEP I Checking for ignition switch voltage supply to the [1][2]power module.



TEST 1 STEP K Checking automatic idle speed motor signal from the logic module.



TEST 1 STEP L Checking automatic idle speed motor signal at the logic module.



TEST 1 STEP M Checking automatic idle speed motor signal at the logic module.



TEST 1 STEP N Checking the logic module ground circuit.

TEST 1 STEP 0 Checking for intermittent failures caused by wiring and/or connectors.

The majority of intermittent failures are caused by wiring and connections. The only way to find them is to try and duplicate the problem. Since the logic module can remember where they are, the ATM and Sensor Test Modes can be used in an attempt to locate them.


^ If the following fault codes do not reappear use the ATM Test Mode as indicated.

Fault Code ATM Test Mode

25 03
26 02
27 02
31 07
33 05
35 04
37 10
42 06
43 01


Once in the correct test mode, wiggle all the connectors and wires in the circuit. When the bad connection or wire is located the ATM test will be interrupted.


^ If the following fault codes do not reappear use the Sensor Test Mode as indicated.


Fault Code Sensor Test Mode

14 ** 08
22 04
23 03
24 05


** When checking the M.A.P. sensor circuit, (fault code 14) apply 10 inches of vacuum
to the M.A.P. sensor before testing.


Once in the correct test mode, wiggle all the connectors and wires in the circuit. When the bad connection or wire is located the display on the readout box will change.



TEST 2 STEP A Checking for fault codes 13 and/or 14-M.A.P. sensor circuit.



TEST 2 STEP B Checking the M.A.P. sensor circuit in the logic module.



TEST 2 STEP C Checking the M.A.P. sensor signal circuit to the logic module.



TEST 2 STEP D Checking the M.A.P. sensor wire to the logic module for an open circuit.



TEST 2 STEP E Checking the 5 volt supply to the M.A.P. sensor.



TEST 3 STEP A Checking for fault code 15 - speed sensor circuit



TEST 3 STEP B Checking the speed sensor circuit to the logic module for an open circuit



TEST 16 STEP A Checking for fault code 21 -oxygen sensor circuit to the logic module.



TEST 4 STEP B Checking the oxygen sensor circuit at the logic module.



TEST 5 STEP A Checking for fault code 22 - coolant sensor circuit.



TEST 21 STEP D Checking for high fuel pressure.



TEST 22 STEP A Checking the oxygen sensor operation.



TEST 22 STEP B Checking for a rich engine operating condition.



TEST 23 STEP A Checking throttle body minimum air flow.