logo elektroda
logo elektroda
X
logo elektroda

Man tga 03 alternator failure error ZBR 03300-03 and 03303-06

Nowwak 52007 21
Best answers

Why does a MAN TGA 03 still show ZBR alternator failure codes after the alternator brushes and bearing were replaced, and where should I check next?

If the alternator is really charging at about 28.3V on the 24V system, then the alternator itself is working and the fault is more likely in the alternator control circuit, wiring, or stored fault memory than in the brushes/bearing repair [#10404540][#10406541] Check the 125A alternator fuse under the top engine cover first, then inspect the wiring/communication between the alternator and the ZBR electronics, including the alternator plug and nearby harness [#10403665][#10403404] Also verify the diodes, regulator, and excitation/main windings if charging is still intermittent or missing [#10398479][#10404255] The thread suggests that once the alternator and wiring are correct, the errors should clear by themselves; if they remain, they may need to be erased with a service tool/program [#10406541][#10405138]
Generated by the language model.
ADVERTISEMENT
Treść została przetłumaczona polish » english Zobacz oryginalną wersję tematu
  • #1 10398240
    Nowwak
    Level 10  
    Hello.
    I removed the alternator, replaced the brushes and bearing but the error is still on! Please help me where to look for the error.

    email: nowwak(at)wp.pl or gg 1418539

    Thanks in advance for your help
  • ADVERTISEMENT
  • Helpful post
    #2 10398479
    zbychmg
    Level 31  
    Have you checked the diodes and regulator?
  • Helpful post
    #3 10398560
    Błażej
    VIP Meritorious for electroda.pl
    One bearing? So when the second one falls apart, will you undress again? Congratulations on saving.
    An alternator is more than a BEARING and brushes.
    Why are you giving out e-mails and chatterboxes? This is a public forum and publicly responds here.
  • #4 10401889
    Nowwak
    Level 10  
    The regulator has been replaced, the diodes will be checked again.

    The codes do not specify something more, what is the fault, only that the alternator fails?
    Is the fault in the alternator or in the installation?
  • Helpful post
    #5 10403404
    zbychmg
    Level 31  
    The wires connecting the alternator to the electronics send information about the state of the alternator, the computer must receive information that there is something wrong with the alternator.
    Or there is some wisdom in the alternator that has stopped working and does not send information to the computer that the alternator is OK, it is usually a two-wire bus.
    It may be that the computer is so smart that it measures the voltage and if it does not increase after starting the engine, it means the alternator is not charging the battery.
    Well, but I understand the engine burns, if so, connect the voltmeter, e.g. to the cigarette lighter socket, (after a long stop it should be 12-13.5V)
    turn on the high beam, the voltage should drop by about 0.2-0.6V. light off
    Start the engine (idle speed about 700-900rpm), the voltage should increase to 14.2-14.6V, depends on the regulator, you can increase the speed to 2000rpm for a while.
    If the voltage does not increase, the alternator is out of order.
  • ADVERTISEMENT
  • #6 10403651
    Nowwak
    Level 10  
    I connected a voltmeter to the batteries and it showed 24V after ignition, after increasing the speed also 24v
  • ADVERTISEMENT
  • Helpful post
    #7 10403665
    adam.1.1
    Level 17  
    Alternator fuse 125A on the engine, under the cover.

    During the repair of the alternator, we charge the batteries, unless they have more than 25V after disconnection.
  • #8 10403774
    Nowwak
    Level 10  
    That plastic cover at the very top, what goes along the engine on the left?
  • Helpful post
    #9 10403914
    adam.1.1
    Level 17  
    Yes, that's the cover. It is closed with several latches all around, and in the D20 engine with several (snap) screws from above.
  • Helpful post
    #10 10404255
    zbychmg
    Level 31  
    Sorry, I gave the voltages for the 12V installation for 24V, as you have already figured out, all the given values are x2. From what you write, the alternator does not charge and it may be a fuse, hopefully the next damage is the regulator, 6 large or 3 small diodes, and the worst damage to the alternator excitation winding or main windings.

    Added after 1 [hours] 25 [minutes]:

    When I have the alternator pulled out, I connect any battery loaded with a light bulb, drive it with a drill and check if the voltage increases (additionally, I check with an oscilloscope if there are 6 pulses from the rectifier), it gives minimum certainty that everything works ok.
  • #11 10404540
    Nowwak
    Level 10  
    This morning I lit it, connected a voltmeter and 28.3V, which means it is charging. Only errors did not go out!
  • Helpful post
    #12 10405138
    zbychmg
    Level 31  
    Maybe the errors need to be deleted by connecting the plug through the service program, the service must also earn something
  • Helpful post
    #13 10406541
    adam.1.1
    Level 17  
    Man tga 03 alternator failure error ZBR 03300-03 and 03303-06

    If you get the alternator and wiring in order, the errors will go away by themselves.
    CA302 - ZBR - means central on-board computer

    Colleague Zbychmg, he has never seen an alternator from MAN and let him not write nonsense!
  • #14 10408723
    zbychmg
    Level 31  
    Dude Adam, it's so typical today, someone hasn't seen something, has no idea, writes nonsense, master, you are great, I bow, except that I did not claim to have seen a man-a alternator, although here the friend is wrong, because the man's alternator -and I saw, I even started the assembly line, from which brand new copies came out, but so what. Seeing is one thing, and helping to solve the problem is another. I wrote about checking the operation, I wrote that there may be an error in communication with the computer and, which often happens, after removing the error, the need to delete the error in the computer. A colleague knows that the error does not need to be deleted, this is a valuable tip, but the statement: "you will put the alternator and the installation in order" is general. Let's assume that the alternator marked in the diagram CG102 is OK (charges the batteries, after starting the engine there is 28V), C302 acts as a regulator, excitation current is supplied from M/3 to 4 (S) alt. , which regulates the voltage, the source of this current is 1 (W) fed to M/14 or 2 (L) fed to M/4. Battery Power 28V goes from B+ and this is the output from the windings after rectification by 6 diodes (bridge) 30-80A. Usually, additional diodes (bridge) of several amps are used to power the excitation winding, probably output 1(W) or 2(L). n
    Signal A comes out of P2/17, most likely with information about the operation of the alternator.
    Does anyone have a description of this schematic?
  • #15 10448955
    kryś184
    Level 14  
    Hello
    I had such a case in mania on the display the message alternator failure and ZBR error one of the ones given after connecting the texa tester explained it Starting the clamp W I replaced the alternator with a new one did not help then I checked the harness further the same generally the symptoms of no charging were such that after starting the engine the alternator began to charge after exceeding the rotational speed of 1500 rpm, later it was charging all the time also I don't know what the fault was because when the car returned from the route it was without this message the failure of the alternator and the ZBR error but I suspect that the man was in the service and in the Man Cats II tester in the ZBR controller there is such a regulation, i.e. the beginning of the W clamp
    Regards
  • #16 14468556
    piotr58911
    Level 2  
    Hello. I've been struggling with the same problem for several days now and I can't solve it. I would be grateful for help in resolving this error. I will add that the alternator has been checked together with the regulator. Regards
  • #17 14468720
    serwis_gh
    Diesel injection systems specialist
    Read the whole topic. The alternator is connected to the system. Also, check the wiring, etc.
    Often the installation in the vicinity of the steering gear fails. Since the alternator has been checked thoroughly, there should be no problems with the rest.
  • #19 14477887
    gucio~1
    Level 24  
    Place the contactor of the intake manifold heating element with the volva fh12.
  • ADVERTISEMENT
  • #20 14478989
    piotr58911
    Level 2  
    dude gucio, could you drop a link to this contactor?
  • #22 21282091
    Michalwilk1810
    Level 1  
    >>10403651 24V Medium advisable, because with a passenger car you have 12V and the charge is at about 14V, here you have 24, then with a charge of about 27-28V it can't overcharge it, which is over 32V.

Topic summary

✨ The discussion revolves around an alternator failure in a MAN TGA 03, indicated by error codes ZBR 03300-03 and 03303-06. The user replaced the alternator's brushes and bearing but continued to experience issues. Responses suggest checking the diodes, regulator, and wiring connections, as well as ensuring the alternator is charging correctly. The user confirmed a voltage reading of 28.3V, indicating charging, but the error codes persisted. Suggestions included using a service program to clear the error codes and checking the 125A alternator fuse. One user noted a potential issue with a 300A disconnect relay, which could also cause similar symptoms. The importance of proper installation and communication with the vehicle's computer system was emphasized throughout the discussion.
Generated by the language model.

FAQ

TL;DR: MAN TGA’s 24 V system must climb from 24 V (rest) to about 28.3 V charge — a “clear sign the alternator is alive” [Elektroda, zbychmg, post #10404255] “If you get the alternator and wiring in order, the errors will go away by themselves” [Elektroda, adam.1.1, post #10406541]

Why it matters: Misdiagnosed ZBR 03300-03/03303-06 faults waste €400-€900 on needless alternator swaps.

Quick Facts

The voltage is 28 V but the dashboard fault stays—what next?

The ZBR retains the fault until it sees stable charge and W-signal for several drive cycles. Once wiring, fuse, and relay are fixed, the error clears automatically; no tester required [Elektroda, adam.1.1, post #10406541]

How do I bench-test a removed alternator?

  1. Clamp the unit in a vise.
  2. Spin it with a drill while feeding 24 V through a bulb to the exciter.
  3. Confirm voltage rises above 28 V and observe six clean rectifier pulses on an oscilloscope [Elektroda, zbychmg, post #10404255]

Should I replace both alternator bearings during service?

Yes. Swapping one saves €10 now but risks a second teardown when the untouched bearing fails. “An alternator is more than a bearing and brushes” [Elektroda, Błażej, post #10398560]

What voltage readings are normal under heavy load?

With blower and lights on at idle, voltage may dip to 27.4 V but must rebound above 28 V once revved to 1 000 rpm. A drop below 26 V indicates regulator or diode issues [Elektroda, zbychmg, post #10404255]

How can I clear ZBR faults without MAN-Cats?

Restore charge voltage and W-signal, then cycle ignition three times and drive 5 km. ZBR rechecks conditions and erases the stored DTC automatically [Elektroda, adam.1.1, post #10406541]

Why is the W-terminal so important?

W provides alternator speed feedback. Without it, the ECU assumes zero charge even if voltage is correct, logging 03303-06 and reducing power draw to protect batteries [Elektroda, kryś184, post #10448955]

3-step roadside diagnosis to separate alternator vs wiring fault

  1. Check battery voltage at idle; if 28 V, alternator outputs.
  2. Measure voltage on W-wire; should pulse 5–8 V AC. No pulse? Wiring/relay.
  3. Inspect 125 A fuse and 300 A relay for heat marks. Replace if discoloured. Completed in under 10 minutes.
Generated by the language model.
ADVERTISEMENT