Diagnostics
`29C256`
the ATMEL AT29C256 chip is the de facto FLASHROM chip in use. It uses a 5V programming voltage, can be erased repeatedly...
1991 PM6 ECU Diagnostic LED (CEL) Blinking Routine
Technical explanation of the diagnostic LED/CEL blink routine inside the 1991 OBD0 PM6 ECU codebase.
203 AC
Author: PRCIVIC Date: 052803 21:46 Ok I have commented the AC routine posted for the benefits of those with no assembly...
6260A Testing
J. Wong: about the 6260A thing... if you take a look at the code (91 PM6ECULEDCEL) that flashes the ECU LED for codes yo...
66k Assembler Docs
Here you can find all the documentation on the Oki 66K achitecture that we have been able to find. If it isn't attached...
91PM6
Describe 91 PM6 here. 91 PM6 Target Idle describes how to set the target idle in a PM6. Similar to 91 PM7 Target Idle 91...
91PM6 Target Idle
Author: xtensive Date: 010403 20:47 Ok, here's what I found: That whole area is data tables. The routine that calls the...
A5
A5h (opcode 'A5' in hexidecimal) is the "reserved" opcode of the 8051 instruction set. This means it is NOT a valid inst...
Absolute Pressure
Absolute Pressure refers to pressure measurements made on a scale where Absolute Vacuum = 0. Atmospheric Pressure is app...
AC Cut Routine
Author: evo (61.88.2.177) Date: 030403 22:15 After much thought, ive decided to share my AirConditioner Cutoff routine.
Add Boost
crome scripts work on p06, p28, p30 (edm, jdm, usdm), p72; it recognizes the rom as do most other Rom editors.
Add Knock To P30G00
On 1720 or 11f0 I've: remove R140, R141 10k add R107, R115, R116 220R I also add (they may not be essential): C94 4u7 16...
Adjust PR4 Pa Sensor
Dave Blundell sez "Vernon (deluded) sent me much of this info." As a rule of thumb, 90 PR4s have external PA sensors, an...
API
Application Programming Interface An API is a set of functions (usually present in a DLL or other code library) that you...
ASM662
ASM662 is an Oki 66201/66207/66301 assembler/disassembler which is still a work in progress. It's released under the BSD...
Auto Or Manual
A hardware/software interaction will determine whether a program in an ECU behaves as a manual or auto.
Batronix USB Programmer
The Batronix USB Programmer is a slightly more polished product than their Eprommer3.3. As of October 9, 2003, it costs...
Check Sum
A Checksum is a very basic form of error checking. A checksum is calculated by adding the values of a ROM together, with...
Checking Error Codes
https://web.archive.org/web/http://forum.pgmfi.org/viewtopic.php?t=4886See also Honda Error Codes
Disable VTEC VSS Check P30 203
Author: doc 071003 15:21 Did i? Ok, in a 203 or 209 rom, you can change the location 6010 (hex) from 00 to FF to bypass...
DIY Engine Simulator for ECU Bench Testing
A detailed build guide for a DIY hardware Engine Simulator (ECU Stimulator) used to bench-test and debug Honda OBD0, OBD...
ECU Backup Processor
Honda ECUs are engineered with many levels of redundancy. There is a Backup processor (labeled NEC BACK0004 in most OBD0...
ECU Trouble Codes
Reading and interpreting OBD1 ECU diagnostic trouble codes.
ECU Troubleshooting
Diagnosing a Honda ECU that will not run the car.
ECU-Code Compatibility
Most honda ECUs can run code from other ECUs of a similar age, and similar family. Civics and Integras generally can sha...
EEPROM
Electrically Erasable Programmable ROMBasically, an EPROM that can be erased using a Rom Burner or similar device.
Engine Coolant Temperature
The Engine Coolant Temperature (ECT) sensor measures how warm (or cool) coolant passing through the motor is.
Find Page
Here are some good starting points for browsing. How To Use Wiki gives you the quick lowdown on Wiki markup.
Full Throttle Shift
Full Throttle ShiftThis is simply an extension of the concept behind FullThrottle Launch (aslo called Launch Control) th...
Further Reading
So you want to learn more about EFI theory, ECUs, or just stuff in general. This is intended to be a place to put links...
Fuzzy Pages
The titles of all pages are searched to find those which are similarly spelled or similar sounding (english). Fuzzy Page...
Hex File
A "hex" file is a file encoded in Intel Hex format. The Intel HEX file is an ASCII text file with lines of text that fol...
Hon Data
Hondata are the current (nov 03) commercial leaders in stock Honda ECU development and reprogramming.
Honda Diagnostic Trouble Codes (DTC) Reference Guide
A complete reference list of Honda OBD0, OBD1, and OBD2 diagnostic trouble codes (DTCs), including CEL flash counts and...
Honda OBD0 and OBD1 ECU datalogging overview
Historical overview of OBD0 and OBD1 Honda ECU datalogging methods, ports, adapters, and software.
Honda/Acura Trouble Codes
How To Check Obd1 Ecu Codes
How To Use Wiki
''"Wiki wiki"'' means "quick" in Hawai'ian. All you really need to know is: To edit any page click on the Edit Text link...
Injector Test Circuit
The Injector Test Circuit is present in USDM ECUs to determine whether injectors are connected to the ECU. Responsible f...
Joel Eck
I'm Joel Eck, my PGMFI handle is 90wagon. It took me entirely too long to figure out 90wagon was not a valid wikiword, w...
Label Decode
You can find out a lot from reading the label on a OBD1 ECU. This applies mainly to the Civic ECUs...
Limp Mode
Aka "Limp Home Mode" Limp Mode is the mode of operation when the ECU's CEL is lit solid red indicating a major malfuncti...
Link Icons
Link Icons are an optional new feature of Php Wiki. When activated, icons will be displayed in front of URLs to indicate...
Manual Checksum
There are two ways to fix a checksum error. The first is to change the program of the ROM in such a way that the checksu...
Nico Analyze
Author: XDEep first thanks to nico for a great tool. the mishap im talking about is when you drag the scrollbar up and d...
OBD0 16-Bit RPM Formula
RPM to 16-bit hex value conversion formula for OBD0 Honda ECUs.
OBD0 Code Compatibility
Can you run code from one OBD0 MPFI ECU in another? The short answer to this is yes. The following has been tried before...
OBD0 Stock Datalogging
The serial interrupt code in the stock ECU is very simple. A 1 byte hex address is sent to the ECU, and the ECU responds...
OBD0 VTEC EC Us
The OBD0 VTEC ECU's are the PR3 and the PW0. These ECUs ran the B16A1 in OBD0 cars from 8991. There is no code interchan...
OBD0BACKUP
the BACK0004 Processor made by NEC is present in all OBD0 MPFI ECUs. It runs the car when the CEL is lit solid red and t...
OBD0MPFI
There is a very distinct family of ECUs found in 8891ish OBD0 hondas. The main characteristics of this family: Oki80 C15...
OBD0VSS
Author: George Date: 120302 22:36 Vehicle Speed Sensor (VSS), stored in RAM location 06Ch does appear to be linear (to m...
OBD1 Civic Integra EC Us
Almost all OBD1 ECUs used in 9295 Civics and integras (but NOT preludes, accords, legends, etc.) are more or less electr...
OBD1 P72 ECU Debug Mode & ROM Configuration Switches
Technical analysis of the diagnostic debug mode and ROM configuration byte switches in the OBD1 Honda P72 ECU.
Oki80C154
MCU used in OBD0 MPFI ECUs that has zero internal code memory. requires the use of an external EPROM It is mostly 8051 c...
Oki83C154
MCU used in OBD0 MPFI ECUs that has 16k onchip code memory. Usually copy protected, but there are Mcu Readers.
P2P
P2P (Stock Bin) This Bin is based on a P30 with P2P Maps (P2P230) 9698 OBD2 A Civic EX Coupe 9900 OBD2 B Civic EX Coupe...
PH3
THe 8889 Accord OBD0 B20A ECU uses an Electronic Advance distributor. It has an External 27c256 ROM and is oki 80c154 ba...
Php Wiki Administration
Note: Most of the actions on this page require administrative privileges. They won't work unless you have set an admin u...
PK2
Prelude OBD0 B20A ECU. Electronic Advance. External 27c256 ROM. oki 83c154 based pk2 ECU photo.: I posted the Options Cl...