flash7210 wrote:
Quote:
The ECM measures and adjusts the voltage output from the alternator
On 05-06 north American CRDs, the alternator has a built in voltage regulator. The ECM does nothing to control voltage output.
Should the regulator fail, the regulator can be replaced fairly easily.
I replaced my voltage regulator a few years ago. Symptom was flickering lights while driving.
Yes my bad...I will sort of agree with you here
I say sort of because your ago while I had the User name of Billwill I had a long discussion on this site about this issue because the
Theory of operations under the Engine Systems section for 2005/6 KJs still states that the PCM....for gassers....adjusts the voltage.
No mention of the CRDs.
The wiring diagram for the 2005 would appear to show that the ECM is not involved but the Front Control Module sends a signal to the alternator. The wiring diagram for the 2006 shows the diesel alternator getting a signal from the ECM.
I recall that Keith from GDE got involved in the discussion and I seem to remember that he stated that the 2005 CRD gets a "wake-up" signal from the FCM 20 seconds after starting telling the Alternator to start providing current via its internal voltage regulator...the 20 second delay is to give the starter full power to turn the engine over.
Then I seem to recall that Keith said that this was dropped in 2006 and Jeep went back to the old system...as used in Export 2002-2004 CRDS whereby the ECM controlled the alternator voltage via Pulse Width Modulation pulses.
I will see if I can find these old posts from Keith to confirm if I am stating the truth but seeing as I have never worked on a 2005/6 Export CRD here in SA I am not really the Expert here.....USA models may in any case be different so I will bow down to the opinions of USA CRD owners.
Another point that is a bit confusing is whether or not the USA models have the Battery Temperature Sensor fitted under the battery which slightly controls the ECM output....the Theory Of Operations state that this exists...maybe only in the gassers...but the wiring diagrams do not show them. Here is where USA readers here can easily put this question to rest as they would have noticed the presence of this Sensor staring up at them when they removed their batteries.
I had charging problems on my Export 2002 CRD which I traced down to a ground gone missing on this Temperature Sensor.
I will check the part numbers I have for the 2005/6 CRDs to see if they match or not.....I like to know the real status of our KJs as I am a retired Electrical Engineer and like to assist all KJ owners in resolving their problems.