Description

Daewoo B15S, B18S 1999 Service Manual

You’ve got a Daewoo B15S, B18S 1999 Service Manual sitting on the bench because you already know that aftermarket knockoffs cost you billable hours. That bus lost drive power halfway through a route, and you need the actual OEM procedure for the DC-DC converter and logic unit—not some reprint that tells you to “check connections.” This is the real factory publication: 436 pages, published May 1999, with torque specs on page 2 and safety warnings on page 3 that keep you alive.

Torque Specs and Safety: Page 2 and Page 3

Page 2 lists torque specifications for the entire vehicle. Page 3 has the mandatory safety precautions—read and understand all warning plates, use proper lifting procedures for components over 50 lb, and never work under a machine supported only by a hoist. I’ve seen techs skip these and pay for it. Don’t be that guy.

Drive Circuit Diagnostics: Bypass, Control, and Failure Protection

The Systems Operation section covers the drive circuit in detail: bypass circuit, control circuit, current limit, failure protection, flyback circuit, power circuit, and thermal protection circuits. If your bus has erratic acceleration or intermittent shutdowns, start here. The manual walks you through each sub-circuit with factory-level clarity—no guessing about which wire feeds what.

The failure protection circuit alone saved me a full afternoon on a B18S last month. The manual explains exactly how the controller locks out the drive when it senses a fault, and the step-by-step procedure to clear stored error codes after the repair. You need that diagnostic sequence, and it’s not in any third-party PDF.

For the power train side—drive motor, final drives, wheel bearing adjustment—the manual devotes an entire section (SB2193E01) with specifications and disassembly procedures. If you’re swapping a motor or setting backlash, the pinion depth check procedure is laid out with actual measurement tolerances. Page numbers vary, but the index gets you to the right table fast.

Does This Manual Cover the Hydraulic System?

Yes. Section SB2194E00 covers hydraulic control valve, pump, pump motor, lift cylinders, and priority valve. If your bus has a hydraulic issue—say the lift cylinders drift or the pump motor draws too much current—the manual provides component tests and adjustments. The hydraulic pump motor circuit is diagrammed separately, including the control circuit and flyback circuit.

7 Systems Documented Across 436 Pages

That’s not a sales pitch. The manual splits into Drive & Control System (SB2192E00), Power Train (SB2193E01), Vehicle Systems (SB2194E00–SB2197E00), and Operations & Maintenance (SB2084E01). Each section has its own index, specifications, system operation theory, testing and adjusting steps, and troubleshooting problem lists. You get built-in diagnostic operation instructions for accessing stored error codes, component tests for contactors, current sensors, transistors, and the logic unit quick reference voltage check.

For the logic unit alone, the manual covers location, behind-logic unit access, operational circuit elements like accelerator control, battery discharge indicator (BDI), central vehicle monitoring system (CVMS), and contactors. That’s factory-level depth you won’t find in a generic wiring schematic.

Understand the Logic Unit Before You Touch It

One wrong probe with a multimeter on the logic unit can fry the driver board. The Testing and Adjusting section gives you the exact procedure for “Logic Unit Quick Reference Voltage Check” and “Driver Board (On Vehicle)” tests. You don’t guess which pin is which—the manual lists transistor connections, resistor values for PR1 and PR2, and the head capacitor discharge procedure. Discharge that capacitor first: page 3 warns you about stored energy, and the system tests show you how to do it safely.

Aftermarket manuals don’t include the “Self Diagnostics” (lift truck not in operation) or “Run Time Diagnostics” (lift truck in operation) tables. This one does, with the exact fault codes and corrective actions. If you ever needed to erase stored error codes or toggle programmable features (like BDI adjustment or current limit settings), the steps are documented with the factory button sequence.

For the power train, the manual includes drive motor armature tests, brush holder tests, commutator inspection, and thermal switch checks. If you’re tearing down the transaxle, the bearing and gear clearance (backlash) adjustments are specified with measurement tools and tolerances.

And if you need to understand how a manual transmission works on a different vehicle, the Manual Transmission article on Wikipedia covers the basics—but for this Daewoo bus, stick with the OEM data.

Factory OEM Print vs. Aftermarket Reprints

This is the original factory publication from Daewoo, form number SB2190E, dated May 1999. It uses the same documentation that dealerships had on the workbench. Aftermarket companies scan these pages and resell them missing the foldouts, losing resolution on wiring diagrams, and omitting factory service bulletins. Page 1 of this manual lists all included form numbers—SB2003E00, SB2004E00, SB2192E00, etc.—and tells you which supplements might be available. You don’t get that with a reprint. If you want the real spec for the head capacitor charge time or the current sensor resistance, it’s in the original print, not a black-and-white copy.

Related Daewoo equipment? Check out Daewoo Musso Service Manual – Factory OEM Specs for 1465-Page Workbench, the Daewoo 661LA, 662NA, 662LA 2000 Service Manual – Factory OEM, and the Daewoo 470LC-V 2001 Service Manual – Factory Specs for Excavator Maintenance.

FAQ

Does this manual include wiring diagrams for the entire bus?

Yes, the electric system schematic is listed in the TOC under Vehicle Systems (form SB2197E00). Specific circuits like actuation, horn, hour meter, and hydraulic pump motor are diagrammed in the Systems Operation section.

Can I use this to program the controller after replacing the logic unit?

Yes. The manual covers programmable feature settings – activating default settings, setting procedure option features, and configuring the accelerator control linkage, BDI adjustment, current limit test, and electrical braking current test. The driver board test procedures (off-vehicle and on-vehicle) are included. Follow the steps in order or you’ll lock the controller.

You’ve got the bus pulled into bay 3 and the clock is ticking. Skip the generic PDFs and the forum advice. Access the Factory Manual from AutoRepairManuals and get the torque specs, the diagnostic flow charts, and the safety procedures you need to finish the job right the first time.