I am having some electrical issues on my 2005 jeep liberty crd. it has only 30K milage. i replaced new optima battery 6 months ago. now i have to manually charge the battery every 3 days. i took it to the interstate where i purchased the optima battery, they tested for 48 hours and said the battery is in great condition. they did some alternator testing on my jeep and told me the battery is not getting charged.. 0Amps is coming from alternator. they said its very strange. looks like my alternator is dead or the alternator pulley/decoupler went bad and hence no current generation. how can i find out if alternator decoupler was bad or not. i have some generic OBD software..is it going to throw some faults for this issue.

also the interstate tech said, i have some drainage issue. the car is drawing around 1A after switching off all devices. is it normal? i am not sure how to diagnose this drainage issue. any hints is really appreciated. i can try attaching an ampere meter in series and start pulling fuse one by one and see which one is culprit! and start tracing the circuit from there.

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2005 Liberty CRD
Airbox Mod

I would take the serpentine belt off of the alternator and manually turn the alternator pulley to see if the internals of the alt move with the pulley. The pulley is a weak link in the charging system and is known to go bad. The pulley also starts to make noise when it is starting to go. Some auto parts stores also have an alternator testing bench to see if it is properly charging. But that means you have to take the alt. off of the car. Good luck

I had to replace the pulley in Aug of 08 the redesigned part # is 53013554-AA cost me $ 53.00 and the plastic cap covering the nut for the pulley is 53013559-AA $ 1.90 Remember the pulley is left hand thread so when you replace it it only needs to be hand tight the direction of the belt will always keep it tight.

Thanks very much for the part numbers. I am going see if the pulley gave up or not.

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2005 Jeep Liberty CRD
Swapped with 2002 3.7L Airbox,Fumoto Valve, Provent hanging next to battery, Samco turbo hoses, Running on B100 since 2006

2002 VW Jetta TDI
oldnavy CCV, Fumoto Valve, Running on B100 since 2006

The circuit diagram that I have for the 2002 Liberty, gas or Diesel, shows that the thick green wire that goes from the positive connection of the battery to the alternator....ie. the the wire that carries the charge to the battery....is actualy a
Fusable Link! check that this link has not blown ie. disconnect both ends and measure for continuity.
I am not sure what you have to do if this link is blown...buy another I suppose.
They probably do this for safety reasons.

Edit to add: Also check the connector plug at the rear of the alternator (two wire) is in firmly...this supplies current to the field coils.
This varying current (Pulse Width Modulation) to the field coils is supplied by the ECM in the CRD and the PCM in the Gas versions so it may be worth your while to disconnect the battery and replug the two connectors on the ECM.
Most likely cause though is the alternator pulley as several members here have stated above.

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2002 Export CRD 2.5 Sport