Description

1990 BMW 735i, 735iL, 750iL Electrical Schematic

I have pulled a lot of wiring diagrams off the internet for customers. They come from forums, scanned copies of copies, third-party reprints. Every single one has a missing pinout, a wrong color code, or a splice that doesn’t exist on the car. If you are working on a 1990 BMW 735i, 735iL, or 750iL, you need the real document. The BMW 735i, 735iL, 750iL 1990 Electrical Schematic from the factory is what sits on my bench when a E32 comes in with a no-start or a dead short. It is 475 pages of actual OEM wiring data, not a summary.

475 Pages of Factory Wiring Data

This manual has an index on page 0100-00 that lists every component and its section. The Systematic Troubleshooting section (0130) gives you a process to follow instead of replacing parts at random. The symbol chart (0140) explains the BMW-specific electrical symbols used throughout. From Power Distribution (0670) to Connector Views (8500), every page is from the original BMW print. No aftermarket copy.

No more chasing ghosts.

Does This Manual Cover the Transmission Control?

Yes. Sections 2460 Electronic Transmission Control (AEGS) and 2465 Electronic Transmission Control (AEGS/EML) are included. These cover the wiring for the 4-speed automatic transmission used in the 735i, 735iL, and 750iL. The diagrams show the transmission control module, solenoids, and speed sensors. If you have a transmission that won’t shift correctly, the electrical side needs to be checked first. This manual gives you the exact pinouts for the AEGS control unit. For the full service data on the transmission itself, see the BMW 7 Series 1988-1994 Service Manual.

Systematic Troubleshooting: The Correct Start Point

Section 0130 Systematic Troubleshooting is not filler. It walks you through a logical process for finding electrical faults. Start by verifying power and ground at the component. Use the power distribution charts in 0660 to see which fuse feeds which circuit. Check ground distribution in 0672 for the specific ground point. This process prevents you from throwing parts at a problem. BMW designed this sequence for their technicians. Follow it.

Get the Right Ground Distribution Data

Ground distribution is where I see most DIY mechanics get lost. The manual lists 20 ground points with their schematic locations, starting on page 0672-00. Each ground point like X165 or X166 has a specific location in the car. If you miss a ground, you will get weird electrical behavior. This manual shows you exactly where to look. For general automotive electrical theory, you can read the Automotive Industry Overview, but for the specific grounds on your E32, you need this manual.

3 Reasons to Choose OEM Documentation Over Aftermarket

1. Wire colors are exact. Aftermarket manuals sometimes use generic colors, but this manual matches the factory wiring. When you are probing a harness, the color code has to be right.
2. Component locations are correct. Section 7000 Component Location Chart and 7100 Component Location Views show where every module, relay, and sensor is physically mounted. Aftermarket manuals often miss one or show the wrong location.
3. Connector views are included. Section 8500 Connector Views shows the pin-outs for every connector. You can verify continuity and voltage without a guess. When you replace a battery, check the Automotive Battery specifications, but for the wiring, this manual is your only source.

If you also need the service manual for engine and drivetrain, the BMW 735i 1988 Electrical Troubleshooting Manual covers an earlier production run. The BMW 735i 735iL 750iL 1988 Troubleshooting Manual is another option for 1988 models.

BMW 735i, 735iL, 750iL 1990 Electrical Schematic: What You Get

The manual breaks down the entire electrical system into individual circuits. Starting with section 0670 Power Distribution and 0671 Fuse Details, you can trace power from the battery to each fuse, relay, and component. Sections 0672 Ground Distribution shows every ground point with schematic locations. If you have a module that is intermittent, the ground distribution is where you start. Section 1360 Injection Electronics (DME 1.3) covers the engine control for the 735i and 735iL, while section 1367 Injection Electronics (DME/EML 1.2) covers the V12 750iL. The transmission control sections 2460 and 2465 are specific to the AEGS and AEGS/EML systems. ABS section 3450 and ASC section 3451 are separate. The Central Body Electronics section 6100 covers ZKE functions like central locking, power windows, and sunroof. Every wire color, pin number, and connector view is documented in sections 8500 Connector Views.

Frequently Asked Questions

Does this manual cover the fuel system?

No. This is an electrical schematic manual. The fuel gauge wiring is on page 6200-06, but fuel pump or injector details are in the service manual.

What is the difference between the 735i and 750iL wiring in this manual?

The 750iL has the V12 engine, so it uses different power distribution and has additional sections for DME/EML 1.2, Electronic Throttle Control, and Automatic Stability Control. The 735i and 735iL have the straight-six. Both are covered in separate circuits within the same document. The manual lists components for both variants, so you need to verify which diagram applies to your VIN. The power distribution charts in section 0660 show the differences in fuse assignments and relay positions. If you ignore this and assume the V12 wiring is the same as the six-cylinder, you will blow fuses or damage control modules.

Are the fuse ratings listed in this document?

Yes. Section 0661 Fuse Charts lists every fuse and its amperage. Page 0671-00 starts the fuse details. You will find what each fuse protects and its rating.

Can I use this manual for a 1991 model?

This manual covers vehicles produced from 6/89 to 8/90. After August 1990, there were changes in the engine management and body electronics. A 1991 model will need a different manual. Check the production date on the door jamb.

If your 1990 BMW E32 has electrical issues, you need this manual on your workbench. Stop using faded photocopies from the internet. Access the Factory Manual and get back to fixing cars.