Alternator - Various Fault Codes

Having charged the batteries overnight I checked the voltage at the starter battery at 6.40am this morning. With charger on it was 14.0V and when I turned the charger off it was at 13.11V. I checked at 6.55am and voltage was 12.92V.

I took the old alternator to an auto electrician and they had hoped to have a look at it today but didn't call me so obviously they didn't get to it.

I came home and checked the battery voltage and it was 12.43V. I plugged in the Nanocom and with the ignition on II the live data showed a voltage of 12.0V. I started the vehicle and the battery light remained illuminated. The live reading slowly went up through 13 to 14 and then 15 before peaking at 15.9 when the 'bings' commenced, the dash warning lights came on and the message centre displaye 'communication with transmission lost not all gears available' of some such, then 'park brake fault' etc.

Turned engine off and read the fault codes:

U0010 Medium Speed CAN Communication bus (pending): ECU Instrument Pack
U0132 Lost communication with ride level ctrl module / Lost communication with suspension module A: ECU Instrument Pack
P0626 Generator field terminal - circuit high (intermittent): ECU Engine Management
P1934 Vehicle speed signal (intermittent): ECU - Engine Management
P0563 System Voltage high (pending): ECU - Transfer Case
P0563 System Voltage high (pending): ECU - Auto gearbox
P0500 Vehicle Speed sensor A (intermittent): ECU - Auto gearbox
C1A00 Control Module (intermittent): ECU - Parking Brake
C1A00 Control Module (intermittent): ECU - ABS System
U0402 Invalid data received from transmission control module (pending): ECU - All Terrain Control
U0416 Invalid data received from vehicle dynamics control module (pending): ECU - All Terrain Control
U0403 Invalid data received from transfer control module (pending): ECU - All Terrain Control
U0155 Lost communication with instrument cluster control module (intermittent): ECU Body Control
U0300 Internal control module software incompatibility (intermittent): ECU - Body Control
U0010 Medium speed CAN communication bus (intermittent): ECU Audio Front Control
U2003 Fibre optic communication bus (intermittent): ECU Audio Front Control


So I will now wait until I either have my old alternator returned to me in certified working order or purchase a new one. I will put whichever of those it is in the vehicle. While doing that I will be able to check the wiring of the plug for the alternator which may well be part of the issue.

I will also procure a new starter battery to be used at the same time - to eliminate the current one as a possible cause/problem/influence. Current start battery is a Century DIN85LMF of 780CCA. It was put into the vehicle the day before I purchased in on 1 Sept 2015.

It appears to me that most ecus shut down and most probably due to excessive voltage. I would go straight to the wiring for the connector on the alternator. If the alternator hadn't been swapped then I would suspect the regulator.

Thanks Graeme. At Ean's prodding I found that the battery in our Tarago is the same configuration as the D3 so I swapped that over and with both the DBS connected and disconnected with no accessories or lights on the vehicle does exactly as I described in my post above.

Will check the wiring and plug when we replace the alternator.

Hi Dale, if you swap the alternator and get the same high voltages, start looking for a loose earth cable.

Also measure the voltage at the cranking battery terminals and make sure it is a runaway alternator/regulator.

Also, check the earth from the drive train to the body, I'm guessing there is a large flexible earth strap somewhere down low.?? If that connection is going high resistance it might be attracting gremlins.

Quote:

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Originally Posted by drivesafe

Hi Dale, if you swap the alternator and get the same high voltages, start looking for a loose earth cable.

Also measure the voltage at the cranking battery terminals and make sure it is a runaway alternator/regulator.

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Quote:

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Originally Posted by vee8auto

Also, check the earth from the drive train to the body, I'm guessing there is a large flexible earth strap somewhere down low.?? If that connection is going high resistance it might be attracting gremlins.

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Thanks - will do both.

I am just curious , if we pulled the plug off the back of the alternator , but left the feed wire that goes back to the battery on the alternator then ran the engine would we be able to do any fault finding ?

From what I see on the wiring diagram the 3 wires on the plug feed power to ECU's . I assume that we would see ECU's faulting but would we be able to determine if the alternator has a faulty regulator and be able to measure what charge is at the battery ?

Cheers Ean

There's not much chance of the regulator in both alternators being faulty in the same manner.

Pin 1 of the connector provides the battery voltage to the regulator. You should be able to measure the voltage without the engine running (might need the ign on - I haven't checked the wiring diagram) to confirm that this wire isn't broken. If the voltage isn't the same as measured at the battery then there is a fault with this sense wire.

Pin 2 is a pwm signal from the ecm to the regulator to control the alternator. If no pwm signal is detected (using an appropriate device) then the ecm is not able to provide control.

Pin 3 is a pwm feedback signal from the regulator to the ecm to monitor the alternator. The existence of a pwm signal at the connector does not prove that the ecm is receiving the signal.

Engine earth should not be an issue as the starter runs.

Auto Electrician checked out the alternator and said that the Field Control Unit had failed and it was not worth repairing. He also said the clutch for the pulley had ceased working and so it was locking (no longer a freewheel pulley). The alternator had also got hot at some stage. I have ordered a new alternator and it should be here in Darwin tomorrow.

The old alternator he said is a Denso. It does not have Denso marking on it but does have the part number A-4068. An internet search turned up a Polish website:

https://en.as-pl.com/p/A4068(DENSO)

which confirms Denso but 105 Amp not 150. However mine does have the connector at the rear of the alternator.

A further search says this is the alternator for a Ford Focus 1.8 TDCi :eek2:

That may explain why the pins on mine where upside down to your alternator Ean.

The alternator I have ordered is an aftermarket with a OEM (Denso) Field Control unit, 150 Amp, 8 rib freewheel pulley.

The $620 alternator arrived this afternoon and Ean again generously came down to swap it over. Fortunately he arrived before the downpour. ;)

The issue with the spare alternator turned out to be that the plug with the 3 wires that connects onto the alternator was half broken off and so on a hot Sunday afternoon Ean had inadvertently pulled it off the old alternator and then pushed it on the spare in the same direction. HOWEVER on the spare alternator the plug was 180 degrees rotation to the old unit. Hence the plug was connected the wrong way around!

New alternator, plug on correct way - all is well!