Charging System - No Start/Generator Lamp Flashing
Group: 27Number: 06-01
Date: Mar. 29, 2006
Subject:
No Start, Generator (GEN) Control Light On or Flashing, Electrical Consumers Not Functioning Properly
Model(s):
See Table 1998 --> 2006
Condition
Note:
This Technical Bulletin ONLY applies to vehicles equipped with 90 Amp Bosch or 90 Amp Valeo generators (GEN). If vehicle has generator with different amperage rating (70A, 120A or higher), Do Not Perform this bulletin.
Vehicles equipped with 90A Bosch or 90A Valeo generators may not charge properly under high ambient temperatures and high electrical loads. Vehicle may arrive to the servicing dealership with a discharged battery, but no indication that the generator is malfunctioning. For vehicles equipped with a 90A generator, follow the guidelines outlined below before performing any diagnosis or repairs.
Vehicle will not start, battery is discharged. Generator (Gen) Control Light on or flashing Electrical consumers not functioning. Ambient temperature is greater than 24°C (75°F).
Service
Tip:
This TB should only be performed when vehicle has a battery related issue; meaning that the battery was discharged and requires charging or replacement per Midtronics tester (MCR34OV or In-Charge 940). If the generator must be replaced as instructed in this bulletin, the claim must be accompanied with a Midtronics test code showing that the battery required charging or replacement. Failure to include the Midtronics test code may result in a denied claim.
Test Plan A - Battery check.
1. - Verify vehicle has no start condition due to a discharged battery or battery related issue (generator control light on, or flashing). If yes, go to step 2. If no, do not complete this TB.
2. - Test battery using Midtronics tester.
Perform action as directed by Midtronics tester to remedy battery condition. This step must be completed before proceeding to step 3! Go to step 3.
3. - Determine Test plan based on servicing dealer location.
^ For servicing dealerships located in any of the following states: Alabama, Arizona, California, Florida, Georgia, Hawaii, Louisiana, Mississippi, Nevada, New Mexico, Oklahoma, and Texas, perform Test Plan B.
^ For servicing dealerships located in all other US states or Canada, perform Test Plan C.
Test Plan B - only pertains to the 12 US states listed above. All other states and Canada, use Test Plan C.
1. - Verify vehicle is equipped with a 90A Bosch or 90A Valeo generator. If yes, go to step 2. If no, do not complete this technical bulletin.
2. -Locate 90A generator part number installed in vehicle. Using Table 1: Generator Reference Table, verify generator part number is listed in table. Locate replacement generator part number using same table. Go to step 3.
Note:
If generator part number is not listed in Table 1, contact VW Helpline for further assistance.
3. - Replace generator with replacement part number from Table 1, see Repair Manual Group 27 - Starter, Generator, Cruise control. Do not perform any diagnosis on existing 90A generator in vehicle. Go to step 4.
Tip:
If generator replacement part does not fit properly in vehicle, contact VW Helpline for further assistance.
DO NOT use any other part number as a substitute other than the part number indicated in Table 1.
DO NOT use remanufactured part number, otherwise warranty claim may be denied.
4. - After generator has been replaced:
^ Restore electrical power
^ Clear DTCs
Test Plan C - only pertains to all other US states not listed above and Canada.
1. - Verify vehicle is equipped with a 90A
Bosch or 90A Valeo generator. If yes, go to step 2. If no, do not complete this TB.
Tip:
Connect the URDI test probe and the 500 amp current probe to the VAS 5051 tool to measure voltage and amperage output as follows:
2. - Vehicle must be at normal operating temperature and ambient temperature should be greater than 24°C175°F.
Using a VAS 5051 select Test
Instruments from display screen
- Connect red test lead to B+ terminal on back of generator.
- Connect black test lead to battery negative (-) terminal.
- Connect 500A current clamp probe to measure (amperage) output of generator.
- Lower hood so that heat can build up in engine compartment. Failure to perform this step may result in erroneous readings.
Note:
If servicing dealership has an air conditioned shop area, it my be necessary to take the vehicle outside when taking voltage and current measurements; otherwise the resulting outcome may be erroneous readings.
- Monitor charging voltage and current during the next steps:
a - Start engine and turn on (at a minimum) the following consumers (headlights, radio (at half volume or more), A/C, and rear defrost.
b. - Allow vehicle to idle for 15 minutes.
Charging voltage should have dropped to less than 12.5V
c. - After 15 engine idling minutes, increase the engine RPM to 2000 while monitoring charging voltage and current for 20 seconds
Did the charging voltage increase to a value of 12.9V or higher within 20 seconds?
- If YES, Did output current increase to a value greater than 75 amps?
^ If YES, Charging system operating properly, no further action required.
^ If No, Generator is not functioning properly, continue to step 3.
3 - Locate 90 amp generator part number installed on vehicle.
- Using table 1, Generator Reference Table, verify generator part number is listed in the table.
- Locate replacement generator part number using same table,then Go to Step 4.
Tip:
If generator part number is not listed in Table 1, contact VW Helpline for further assistance.
4 - Replace generator with replacement part number from Table 1, see Repair Manual Group 27 - Starter, Generator, Cruise control, and restore electrical power.
^ Restore electrical power & Clear DTCs
Note:
DO NOT use any other part number as a substitute other than the part number indicated in Generator Reference Table 1.
DO NOT use remanufactured part number, otherwise warranty claim may be denied.
Instructions listed on right side of Generator Reference Table 1 are directed at all generators listed.
When procedure applies to vehicles within the New Vehicle Limited Warranty, use the table.