BOSCH EZ129K
1) Disconnect coil wire from distributor cap. Put coil wire
next to ground and operate starter motor. If spark is present, check
distributor rotor and cap. If spark is not present, go to next step.
2) Connect voltmeter between ignition coil connector terminal
No. 15 (Red wire) and ground. Turn ignition on. If battery voltage is
not present, check voltage supply to ignition coil. If battery voltage
is present, turn ignition off and go to next step.
3) Connect voltmeter between ignition coil terminal No. 1
(Blue wire) and ground. Operate starter motor. If about .7-1.3 volts
are present, repeat test using new ignition coil. If about .7-1.3
volts are not present, turn ignition off and go to next step.
4) Disconnect engine speed sensor connector located close to
flywheel. Connect an ohmmeter between sensor terminals. If resistance
is about 200-400 ohms, go to next step and check Camshaft Position
Sensor (CMP) signal. If resistance is not about 200-400 ohms, replace
sensor.
NOTE: Engine speed sensor is also known as Vehicle Speed Sensor
(VSS) or impulse sensor.
5) Remove intake hose. Bend aside rubber sleeve on CMP
connector. Connect voltmeter between connector terminal No. 2 and
ground. See Fig. 4. Operate starter motor. If voltage reading varies
between 0-5 volts, go to step 7). If voltage reading does not vary
between 0-5 volts, go to next step.
Fig. 4: Identifying Camshaft Position Sensor (CMP) Terminals
Courtesy of Volvo Cars of North America.
6) Connect voltmeter between CMP connector terminal No. 3 and
ground. Turn ignition on. About 10 volts should be present. Turn
ignition off. Connect an ohmmeter between CMP connector terminal No. 1
and ground. Ohmmeter should show about zero ohms. If voltage supply
and ground are okay, repeat test using new CMP. If voltage supply and
ground are not okay, reconnect intake hose and go to step 9).
7) If voltage reading varied between 0-5 volts in step 5),
disconnect power stage connector at ignition coil. Bend back rubber
sleeve on connector. Check ground supply by connecting ohmmeter
between connector terminal No. 1 and ground. See Fig. 5. Ohmmeter
should indicate zero ohms. Check voltage supply by connecting
voltmeter between terminal No. 3 and ground. Turn ignition on. Battery
voltage should be present.
Fig. 5: Identifying Power Stage Connector Terminals
Courtesy of Volvo Cars of North America.
8) Check power stage control signal by connecting voltmeter
between terminal No. 4 and ground. Operate starter motor. Voltmeter
should indicate .7-1.3 volts. If ground, voltage and control signal
are okay, repeat test using new power stage. If ground connection and
voltage are faulty, check wiring. If control signal is not present, go
to next step and check ECU input and output signals.
9) Connect Breakout Box (981 3190) and Adapter (981 3195) to
distributor ignition ECU. See Fig. 3. Turn ignition switch to OFF
position. Distributor ignition ECU is located in right side of engine
compartment. Remove ECU cover. Disconnect distributor ignition ECU
connector. Visually inspect all terminal connector sleeves to ensure
no terminals are damaged.
10) To install breakout box, remove distributor ignition ECU.
Press adapter onto distributor ignition ECU and pull lead upward
through slot beside module. Press distributor ignition ECU, with
adapter connected, into connector in bottom of ECU box. Connect
breakout box to adapter 60-pin connector.
11) Ensure ignition is off. To check ECU input and output
signals, connect ohmmeter between breakout box terminal No. 20 and
ground, then between breakout box terminal No. 29 and ground. Ohmmeter
should indicate about zero ohms in both cases.
12) Ensure ignition is off. Connect ohmmeter between breakout
box terminals No. 20 and 2, and between breakout box terminals No. 20
and 15. Ohmmeter should indicate about zero ohms in both cases.
13) Ensure ignition is off. Connect voltmeter between
breakout box terminals No. 20 and 10. Battery voltage should be
present. Turn ignition on. Connect voltmeter between breakout box
terminals No. 20 and 30. Battery voltage should be present.
14) Check engine speed sensor signal by connecting voltmeter
between breakout box terminals No. 1 and 2. Operate starter motor.
Voltmeter should indicate 300-400 millivolts. If signal is not
present, check sensor. See Code 1-3-1 diagnosis procedures in the
G - TESTS W/CODES article. If signal is present, go to next step and
check Camshaft Position Sensor (CMP) signal.
NOTE: Engine speed sensor is also known as Vehicle Speed Sensor
(VSS) or impulse sensor.
15) Connect voltmeter between breakout box terminals No. 20
and 4. Operate starter motor. Voltage should vary between 0-5 volts.
If voltage is okay, go to next step. If voltage is not okay, connect
voltmeter between breakout box terminals No. 20 and 14. Voltmeter
should indicate about 10 volts. If voltage is present, but signal is
not present, repeat test using new CMP. If voltage is not present,
repeat test using new ECU.
16) If voltage was okay in step 15), connect voltmeter
between breakout box terminals No. 20 and 43. Operate starter motor.
Voltage should indicate about 5-7 volts. If voltage is not present,
repeat test using ECU. If voltage is present, ignition system is
operating properly.