New member looking for help: XJSC 1987
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The following 2 users liked this post by Greg in France:
Doug (12-15-2017),
orangeblossom (12-15-2017)
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Lucas AB14
Www.everydayxj.com is a source I am about to check out...., How do you test this device. I still have mine just seeing if it work having starting problems......,
#6
Join Date: Mar 2008
Location: Pacific Northwest USA
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Assuming you have a 'no spark' situation....
I don't know how to test the amplifier but you can make some checks of the ignition system which can narrow down the suspect list. This is pretty much just a paraphrasing of what's in the service manual
- With the key 'on', do you have 12v at the coil "+" post? You should. If not, look for a problem at the ignition switch or wiring between the switch and the coil
- Remove the wires from the coil "-" post. With the key on do you have 12v at the "-" post? You should. if not you have a faulty coil.
- Reconnect wires. Using a test light or volt meter on the coil "-" post, does the light flicker slightly (or meter show up-down voltage) when cranking the engine? It should. If not, the amp or the pickup coil (inside the distributor) is faulty.
- To test the pickup coil you'll have to disconnect the 2-wire connector on the wiring coming out of the distributor. You probably won't even be able to see the connector without first removing the cruise control bellows. Anyhow, use an ohm meter to check the resistance of the pickup coil. it should be 2.4 to 4.8 ohms. If out-of-range, it's faulty and must be replaced.
- If the pickup coil is OK then that leaves the amplifier as the culprit. The most common problem with the amplifier is failure of the GM ignition module residing inside, AC Delco number D1906
However....
Don't replace ANY parts without first carefully checking all relevant wiring connections. It is very common for wiring and connections to degrade with age and engine heat....doubly so on a V12
Cheers
DD
I don't know how to test the amplifier but you can make some checks of the ignition system which can narrow down the suspect list. This is pretty much just a paraphrasing of what's in the service manual
- With the key 'on', do you have 12v at the coil "+" post? You should. If not, look for a problem at the ignition switch or wiring between the switch and the coil
- Remove the wires from the coil "-" post. With the key on do you have 12v at the "-" post? You should. if not you have a faulty coil.
- Reconnect wires. Using a test light or volt meter on the coil "-" post, does the light flicker slightly (or meter show up-down voltage) when cranking the engine? It should. If not, the amp or the pickup coil (inside the distributor) is faulty.
- To test the pickup coil you'll have to disconnect the 2-wire connector on the wiring coming out of the distributor. You probably won't even be able to see the connector without first removing the cruise control bellows. Anyhow, use an ohm meter to check the resistance of the pickup coil. it should be 2.4 to 4.8 ohms. If out-of-range, it's faulty and must be replaced.
- If the pickup coil is OK then that leaves the amplifier as the culprit. The most common problem with the amplifier is failure of the GM ignition module residing inside, AC Delco number D1906
However....
Don't replace ANY parts without first carefully checking all relevant wiring connections. It is very common for wiring and connections to degrade with age and engine heat....doubly so on a V12
Cheers
DD
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