check charging system light

check fusible links in picture they should have twelve volts each side move them around a bit while checking if voltage drops then replace that one. if it continues have a mechanic scan for codes for a can/bus problem, one module may not be talking to other and he will have to find It with a scanner.

I have a 2003 Lincoln Navigator, 5.4 V8,4-wheel drive, 67,000 mi. Recently, the "Check Charging System" alert and a red battery icon appeared on the dash. I had Auto Zone check the battery and alternator. The battery (original) checked good, but the alternator failed. I installed a new (not rebuilt) alternator. After installation, the "Check Charging System" alert is still on. A recheck of the alternator output indicates its performance is good. I also checked the battery water levels, and added a slight amount of water to each cell. What else can cause the alert to activate? I've been told that the alert does not require an error system reset.
Thanks for your help.

Have Autozone scan the PCM, might have set a code for system voltage and it could need to be cleared out.

Here is a guide so you can try it yourself.

https://www.2carpros.com/articles/check-engine-light-clear-codes

Please let us know what you find.

Cheers,

Hello,

It sounds like a bad connection at the alternator plug also there is a fusible link that goes out in these cars, you should check the charge plug at the alternator to make sure it is not melted or burned as well. Here is a guide that will show you how to test the system and a wiring diagram to show you the way on what to check for power.

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

Please let us know what happens. (DIAGRAM BELOW)

Cheers, Ken

clearing the computer fixed my problem.

2004 Lincoln Navigator 60,000 miles
----------------------------------------------------------------
when i accelerate for a pass on the highway a message comes up that says check charging system, also on occasions either one of the headlights will not turn on. ( they are on day time running lights ) but i i turn them off and then back on it turns on. the dealer said they checked everything and even changed the battery. is there anything else that could be causing this?

As for the charging light, if the serp belt slips while accelerating, the light may come on, don't forget a new tensioner while youre at it. The headlight? Possibly a corroded connector at the bulb...

i have a 2003 lincoln navigator , 5.4 v8 2 wheel drive 112000 mi recently the check charging sistem alert and a red battery icom appered on the dash i check the battery and alternator are good what else can cause the alert to activate? thanks for you help.

How did you determine the battery and generator are okay? What tests did you do and what were the results?