Speedometer Pulse Type?
Thread Starter
Instructor
Joined: Dec 2001
Posts: 150
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From: Columbus MS
Speedometer Pulse Type?
Here's a technical question. Anyone know what Speedometer Pulse Type a 1998 C5 Convertible has?
I'm CONSIDERING adding an aftermarket hud system to it, but the unit in question is compatible with 2,4,8,and 16 pulse types. (most vehicles are 4 pulse) Honestly, I don't even know what this is.
Next, Does the ECU have a speed sensor signal? I'm sure it does but these are all required for the system to operate.
Seems like a pretty cool gadget, but I'm not quite sold on it yet.
here is the link: http://www.defi-shop.com/sports/spotsfrm.htm
:confused: :confused:
[Modified by NoVector, 3:24 PM 1/13/2002]
I'm CONSIDERING adding an aftermarket hud system to it, but the unit in question is compatible with 2,4,8,and 16 pulse types. (most vehicles are 4 pulse) Honestly, I don't even know what this is.
Next, Does the ECU have a speed sensor signal? I'm sure it does but these are all required for the system to operate.
Seems like a pretty cool gadget, but I'm not quite sold on it yet.
here is the link: http://www.defi-shop.com/sports/spotsfrm.htm
:confused: :confused:
[Modified by NoVector, 3:24 PM 1/13/2002]
Drifting
Joined: Jul 2000
Posts: 1,517
Likes: 1
From: Stockholm
Re: Speedometer Pulse Type? (NoVector)
I do not know what type of signal that is feed from the PCM to the instrument cluster. But the connector is 35/C2 on the PCM, WHT 0.35 wire. The engine speed input on the instrument cluster is A17. This is taken from the -99 service manual. I assume it's a frequency signal or a fixed frequency that is pulse width modulated but it's only a guess.
One more thing, the speed sensor signal input to the PCM is 7/C1 (High) 0.35 YEL wire and 71/C1 (Low) 0.35 PPL wire. This signal is from a magnetic pickup sensor so if you want to tap it you need to use a simple high gain comparator attached to the 7/C1 0.35 YEL wire. Use the comparator output to connect to whatever you need a speed signal to, the signal will be a frequency that follows the vehicle speed.
I hope this gives you some ideas. :cheers:
[Modified by seanr, 10:42 PM 1/13/2002]
One more thing, the speed sensor signal input to the PCM is 7/C1 (High) 0.35 YEL wire and 71/C1 (Low) 0.35 PPL wire. This signal is from a magnetic pickup sensor so if you want to tap it you need to use a simple high gain comparator attached to the 7/C1 0.35 YEL wire. Use the comparator output to connect to whatever you need a speed signal to, the signal will be a frequency that follows the vehicle speed.
I hope this gives you some ideas. :cheers:
[Modified by seanr, 10:42 PM 1/13/2002]
Melting Slicks
Joined: Mar 1999
Posts: 2,499
Likes: 0
Re: Speedometer Pulse Type? (seanr)
I just checked my '98 Service manual and it says the same thing :cheers:
It also says that the speed sensor is as you would expect on the differential.
Connector C1 is red.
It also says that the speed sensor is as you would expect on the differential.
Connector C1 is red.
Thread Starter
Instructor
Joined: Dec 2001
Posts: 150
Likes: 0
From: Columbus MS
Re: Speedometer Pulse Type? (MMarquez)
Thanks,
Anyone know what pulse rate it is?
BTW, where can I pick up one of these service manuals? Sounds like there is some good info in there.
Thanks for the help. :cheers:
Anyone know what pulse rate it is?
BTW, where can I pick up one of these service manuals? Sounds like there is some good info in there.
Thanks for the help. :cheers:
Melting Slicks
Joined: Mar 1999
Posts: 2,499
Likes: 0
Re: Speedometer Pulse Type? (NoVector)
I got mine from a forum member but they are sold by Ken Fichtner. See this thread and search for manual http://forums.corvetteforum.com/zerothread?id=217393
They are definately worth having :cheers:
They are definately worth having :cheers:
