If you have questions on the 10K ohm resistor contact me. This item can be used with TunerPro RT, TTS Datamaster, TunerCat reflash for LT1, WinALDL, and EFI Live V4(OBD1). On MOST ECMs the 10K ohm resistor either does not affect the ECM operation, OR the 10K ohm resistor is needed for data flow. Q - Why would I want to disable the resistor?Ī - On a few select ECMs the 10K O resistor is not needed for the data flow but does alter the idle speed and timing. Q - Can I disable the 10K ohm A-B resistor?Ī - Yes the 10K resistor can be switched off on the 12 Pin version. Q - Does this cable include the 10K ohm A-B resistor needed on many 12 Pin 160 Baud ECMs?
WINALDL CABLE GM DOWNLOAD
Q.- Will this work with my 94-95 6.5 Turbo-Diesel?Ī - Yes it will however you will have to download and use GMTD Scan Basic (free) or GMTD Scan Tech ($) from I think the baud rate is 8192, so youd have to use TTS-DataMaster. The connector is OBD-II, but as I understand it, the protocol is ALDL/OBD-I. Make sure you order the cable that fits your cars connector. Although the cable arrived, I didnt take it further since, A) Id gotten an Innovate wide-band kit in the meantime (I was looking for AFR values alone), & B) I decided to go down the standalone ECU route. GM used 12 pin OBD1 type and 16 pin OBD2 type connectors on 94 & 95 vehicles. Q - Will this cable work with my 94/95 3800 OBD1.5?Ī - Yes it will.
WINALDL CABLE GM SOFTWARE
There are 3 things needed to access the diagnostic data stream from a GM based On Board Diagnostic 1 ( OBD1 ) system on your 1982 - 1995 car or truck.ġ - A laptop PC with an available USB portģ - A software program running with the correct stream definition for your car or truck The ALDL interface circuit components soldered to board: Here is a picture the resistors, transistors, diode and DB9 connector: WinALDL does NOT speak to newer GM OBD1 vehicles that use 8192 baud communication. One simple scheme is to feed the ALDL data into a single transistor level converter that inverts the data to produce a pseudo RS232 level (varies between 12 Volts and 0). Most older TBI GM computers will speak this protocol. A GM ECM produces a data signal at either a 12 Volt (SES/CEL style level) or 5 volt level (TTL/CMOS levels) that must be inverted and converted to RS232. This problem has cropped up recently, I changed PCMs thinking that my PCM was bad, it fixed it with the new PCM but now the new PCM is having the same issue. This includes but is not limited to vehicles using a 12277165 ECM. Compatible with GM OBDI data streams that use the 8192 Baud, Pin M protocol AND 160 Baud Pin USB to ALDL Cable comes with 5 USB extension cable, and Driver/Software CD. This circuit consisted of two transistors one connecting the "ALDL data" to "RS232 Receive", the other connects the "RS232 Send" to "ALDL Ground". About WinALDL is software to datalog on GM vehicles that use the old 160 baud rate. Since the first circuit performance wasn't great and the whole thing was messy, instead of refining the first circuit i thought i should try a new design. This circuit worked, but for some reason the response was slow, i couldn't make it work with a Usb-to-Serial converter, and on some PCs you can't take power from Pin4 so you have to connect it to 12v external power source (the resistor stays). The simplest ALDL interface circuit i could find consisted of one transistor and two 10k resistors it simply connected the data pin on the ALDL plug to the RxD(Receive Data) port on the RS232 on the PC through the transistor. Īldl has a port for sending data and the RS232 on PC has a receive data pin (RxD) so the easiest way is to connect them directly but since each system uses a different voltage we should put a transistor between them.
I've always wanted to connect my laptop to my GMC van OBD1 based ECU, a little research on the internet lead me to a simple circuit that could make that happen.