Fulltext TSBs

Technical Service Bulletins

TSB
04-18-15
  • ADDING ADDITIONAL BULBS TO TURN INDICATOR OR HAZARD FLASHER CIRCUITS – SERVICE TIPS
Publication Date: September 3, 2004

FORD:
1999-2005 F-Super Duty
2000-2005 Excursion, F-650, F-750

This article supersedes TSB 02-21-9 to update the vehicle model years.

ISSUE:

When adding additional bulbs to the turn signal or hazard flasher circuits, isolation relays must be used in order to prevent damage to the flasher relay module and/or the multi-function switch, and to prevent erratic operation.

ACTION:

The following current ranges must be adhered to on the original flasher circuitry:

  • Minimum rated current for the turn signal (either left or right) is 4.45A, at 12.8V and the maximum rated current is 5.06A at 12.8V
  • Turn signal current draw below 2.83A at 12.8V will cause the flasher to flash rapidly
  • The minimum rated current for the hazard flasher is 4.20A at 12.8V and the maximum rated current is 10.12A at 12.8V
Any additional current load above the maximum rating must use isolation relays. Refer to (Figure 1) for typical relay installation illustration.

WARRANTY STATUS:

Information Only – Not Warrantable




Figure 1 – Article 04-18-15