Water In E-Box - DME Control Module Flooded (41 03 93 (3914))
Publication date: 1994-07-01Reference number: 41 03 93 (3914)
WATER IN E-BOX - DME CONTROL MODULE FLOODED
TECHNICAL SERVICE BULLETIN
WATER IN E-BOX
Model(s): 1992-94 BMW 318i/is, 325i/is
1994 BMW 318iC, 325iC
Group: 41 - Body
Bulletin No: 41 03 93 (3914)
Date: July, 1994
SITUATION
Cases of water entering the E-Box and flooding the DME control module have been reported, usually when the vehicle has gone through a car wash that uses an unusually high volume of water.
This is caused by excessive volumes of water entering the cowl air intake plenum, and overwhelming the drain tube's ability to drain off this water. The water in the intake plenum rises to a point higher than the bottom of the partition that separates the E-Box from the intake, and then flows under the partition into the E-Box. If the volume of water is sufficient, and the time of exposure to this volume is long enough, the DME control module will be flooded out.
It should be noted that the volumes required are far in excess of what could be expected in nature. Also, the volume of water in the intake plenum will often cause water to enter the passenger compartment in the right footwell area, which can go unnoticed because the water ends up under the accessory floor mats.
Vehicles produced after 6/94 have a third drain in the intake plenum to drain off excess water.
CORRECTION
In case of customer complaint, install improved capacity air intake drain hose in right side drain, and install additional drain hose.
- Remove air intake screen, air intake apron, and move wiring harness out of the way on left side of engine.
- Remove cylinder head cover, protecting open area with shop cloths to prevent foreign material from getting into engine.
- Remove the right side drain hose and discard. Carefully peel down insulation on engine compartment bulkhead between the A/C lines and the right side air intake drain hole, exposing the stamp in circular area "1" approximately 35 mm (1.3") to the right and above the right side drain hole "2". Center punch the center of this circular area for drilling. See Fig 1 .
- Drill a 10 mm (.375") pilot hole.
- Using electrician's "1/2-inch Conduit Punch," make 22.2 mm (.875") hole.
- Using electrician's "3/4-inch Conduit Punch," enlarge hole to 28.2 mm (1.11").
- File off all burrs and rough edges, and clean up all metal shavings.
- Paint bare metal with zinc-based primer.
- Put insulation back in place, and with a utility knife cut a hole in insulation to align with hole punched in bulkhead.
- Install new style drain hoses, part number 51 73 8 144 152, in both drain holes, angling the hoses approximately 30° toward the center of the car. The hoses are easier to install if they are lubricated with a light soap solution and fed through from the back side of the hole. Make sure the groove in the hose is properly seated in the hole. See Fig 2 .
- Reinstall all removed parts, replace damaged control unit.
- On tools required, the electrician's conduit punches referred to are available at tool suppliers or electrical suppliers. These are available in several different configurations and brands.
- The reason that the repair procedure uses a 1/2" conduit punch and then enlarges the hole with a 3/4" conduit punch, is because of the size of the pilot hole required. The 10 mm pilot hole is easily drilled, and can be accurately located. The pilot hole required for a 3/4" conduit punch is 19 mm, which cannot be easily drilled or accurately located because the limited space to work in.
- The brand of punch used to test this repair procedure was Greenlee, which is available nationwide. Other brands of punches can be used, but the finished diameter cannot exceed 30 mm. Hole saws are not recommended for this particular procedure.
- As a reference, the Greenlee numbers of the tools used are listed below:
| Gender | Greenlee Tool Number 1/2" Conduit | Greenlee Tool Number 3/4" Conduit |
|---|---|---|
| Arbor | 5008978 | 5004040 |
| Male | 5004006 | 5004008 |
| Female | 5014722 | 5006972 |
WARRANTY STATUS
Covered under the terms of the BMW New Car Warranty.
Defect Code: 41 13 90 48 00
Labor Operation: 00 51 029
Labor Allowance: 24 FRU
Sublet Allowance: $3.00 (for materials. wires ties etc.)