The alternator does not charge the battery unless i unplug the connector that runs to the PCM.
Jul 8, 2023 at 7:59 PM
The alternator does not charge the battery?
2002 FORD TAURUS
WISHFB
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Hi,
That is odd. The PCM simply uses the info to control the idle speed.
The Generator Load Input (GLI) circuit is used by the PCM to determine the generator load on the engine. As generator load increases the PCM will adjust idle speed accordingly. This strategy helps reduce idle surges due to switching high current loads. The GLI signal is sent to the PCM from the voltage regulator/generator.
When you say it's charging, how was it checked? Do me a favor, let me know the voltages at the battery with the engine off and then the engine running.
Here is a link that explains what to do:
https://www.2carpros.com/articles/how-to-check-a-car-alternator
Let me know.
Take care,
Joe
That is odd. The PCM simply uses the info to control the idle speed.
The Generator Load Input (GLI) circuit is used by the PCM to determine the generator load on the engine. As generator load increases the PCM will adjust idle speed accordingly. This strategy helps reduce idle surges due to switching high current loads. The GLI signal is sent to the PCM from the voltage regulator/generator.
When you say it's charging, how was it checked? Do me a favor, let me know the voltages at the battery with the engine off and then the engine running.
Here is a link that explains what to do:
https://www.2carpros.com/articles/how-to-check-a-car-alternator
Let me know.
Take care,
Joe
Jul 9, 2023 at 9:01 PM
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i used a multi-meter with the battery on and alternator plugged in it reads 12.4 and when i unplugged the connector it jumps to 13.8 with the car off 12.4.
Jul 10, 2023 at 6:26 AM
Is there any damage to the connector pins at the PCM? If there isn't, it sounds like the PCM may have an internal short.
I've attached the diagnostics related to the GLI. Take a look through them and let me know if you are comfortable performing them.
Take care,
Joe
See pics below.
I've attached the diagnostics related to the GLI. Take a look through them and let me know if you are comfortable performing them.
Take care,
Joe
See pics below.
Images (Click to enlarge)
Jul 10, 2023 at 9:36 PM
that last step FH5 is that checked on the middle pin (59).
Jul 13, 2023 at 5:59 PM
Hi,
I attached the wiring schematic below, so you have a reference. If I am reading things correctly, it will be the center pin (3-pin connector) and the wire color will be light blue with a red tracer.
Let me know if this helps.
Joe
I attached the wiring schematic below, so you have a reference. If I am reading things correctly, it will be the center pin (3-pin connector) and the wire color will be light blue with a red tracer.
Let me know if this helps.
Joe
Image (Click to enlarge)
Jul 13, 2023 at 9:45 PM
It turned out to be a bad PCM. Thank you for all the help.
Jul 15, 2023 at 5:09 PM
Hi,
Thanks for the update. It's appreciated. I'm glad you found the problem and were able to resolve the issue.
Take care and feel free to come back anytime in the future.
Joe
Thanks for the update. It's appreciated. I'm glad you found the problem and were able to resolve the issue.
Take care and feel free to come back anytime in the future.
Joe
Jul 15, 2023 at 10:18 PM