SAW Voltage

This forum is for discussing ignition setup, tuning, and troubleshooting for MS-II. Click these links for info on GM's HEI, EDIS, direct coil control, others.
Forum rules
Read the manual to see if your question is answered there before posting. Many users will not reply if the answer is already available in the manual.

If your question is about troubleshooting, configuration, or tuning, you MUST include your processor type (MS-I or MS-II) and code version in your post. If your question is about PCB assembly or modifications, you must also include the main board version number (1.01, 2.2 or 3.0). For tuning/troubleshooting questions, please attached a datalog and your MSQ file to your post.

If you have questions about MS1/Extra or MS2/Extra code configuration or tuning, please post them at www.msextra.com Such questions posted here will be moved to: a temporary MSextra sub-forum, where they will be removed after 7 days

The full forum rules are here: Forum Rules, be sure to read them all regularly.
Post Reply
Duffy
MegaSquirt Newbie
Posts: 3
Joined: Fri May 12, 2006 6:16 am

SAW Voltage

Post by Duffy »

Hello

MS II Version 3, code 2.68

I had this set up running perfectly with my Zetec and EDIS 4.

Yesterday the timing became fixed at 10 degress (Limp home mode for the EDIS 4 when no SAW signal received), I've scoped the SAW and instead of 5 volts it's varying between 0.5 and 1.0, the signal is the right shape and position, just too small.

I've reinstalled the embedded code, checked the power supply to the daughterboard (Slap on 5V) but don't understand the board well enough to know where to go next. I've checked steps 59 to 65 in the assembly guide as best I can (Without removing the varnish layer)

Help!!!!!

:)

Thanks!
Top
Duffy
MegaSquirt Newbie
Posts: 3
Joined: Fri May 12, 2006 6:16 am

Re: SAW Voltage

Post by Duffy »

Problem found!

Turned out to be dry joint from the 5v supply from the proto feed.
Top
pb3
MegaSquirt Newbie
Posts: 9
Joined: Sat Feb 04, 2006 9:25 am
Location: Cambridgeshire, UK
Contact:
Contact pb3

Re: SAW Voltage

Post by pb3 »

Duffy, how are you driving your tacho? If from the IDM (EDIS pin 2) did you notice your tacho drop to zero or any strange behaviour? I am wanting to know what can cause the IDM signal to go flat even when ignition events are still occurring. Thus I am wondering if a bad SAW signal would be reported via the IDM signal by the EDIS unit.
Ultima GTR 6.3L / MS-II / v3.0 / B&G 2.871t6 / MT 2.25
Innovate LC-1 / GM IAC / EDIS-8
http://ultima-efi.mysite.wanadoo-members.co.uk
Top
Duffy
MegaSquirt Newbie
Posts: 3
Joined: Fri May 12, 2006 6:16 am

Re: SAW Voltage

Post by Duffy »

Driving it as guessed direct from the EDIS, however I've been having continuing peoblwms with the EDIS still going into limp home mode and the rev counter surging all over the place.

Enquiries are ongoing!
Top
66fb

Re: SAW Voltage

Post by 66fb »

pb3

I think IDM is for "ignition diagnostic..." something or other...so maybe that's how it does report an error.
Top
Post Reply

Return to “MS-II Ignition Setup, Tuning, and Troubleshooting”