I have been researching how to get the Cluster to work, There is so much misinformation on the internet.
My '04 Blue/Green PCM will not control the '01 cluster, Though some mention segment swaps....No follow through on threads I have found.
'99 & up clusters use Serial Data for every gauge besides the Speedometer & Volt gauge.
'98 F-bodies have full analog gauges.
4000 ppm from the PCM for the speedo.
Tach output from the PCM for the Tach.
Oil pressure sensor wired direct to the cluster.
3-wire coolant temp sensor, Has 2 functions, Temp reading to the PCM, And a feed directly to the Cluster.
Volt gauge reads off the ignition voltage to the cluster.
The problem is...How to get the Fuel Gauge to work? The '98 fuel gauge resistor is wired to the PCM, It buffers the signal & sends it on a dedicated circuit to the Cluster.
I have a '98 Trans Am 160mph cluster, This is the research I did....
Fuel Sender OHM's
According to a GM TSB...
'98 Camaro V6 & V8 250-40 ohms
'98 Firebird V8 250-40 ohms
'98 Firebird V6 40-250 ohms
According to AllDataPro
All '99-'02 F-bodies 40-250 ohms
Great, The resistance is backwards. I decided to do a working model. Because I don't trust the info.....
'97-'98 PCM (GM racing, version 1) It has the same service number as a '98 V8 F-body, wired the grounds, Ignition hots, battery hots, & Data link connector.
Powered up the Cluster Ign., B+, & grounds
Wired the fuel gauge output to the cluster.
Used some resistors from Radio Shack to simulate a Fuel Sender.
66.9 ohms, Fuel gauge reads just above empty or 10%
147.3 ohm, Fuel gauge reads half or 45%
214 ohms, Fuel gauge reads almost full or 83%
Either the Ohm range info for a '98 T/A is wrong, Or this "GM Racing" PCM has a non-F-body base tune. I check the VIN with my Tech 2 & it read GM**RACING**VERSION**1......That was weird.
Also double checked the fuel sender that is in the car now, Gauge reads 1/4 tank & the Sender resistance is 123.3 ohms, So it does have a 40-240 sender.
If I use this set-up, The '98 PCM will only work the gas gauge.....I have to find a place to mount it, wire it, & re-pin the cluster plug. I will call it the Fuel Gauge Module
It would be great to make the Truck PCM run the "Serial Data" cluster.
I have access a '00 T/A 0411 PCM for the needed gauge segment.
Any insight on this?
Pics, I was using a 18V dewalt battery, The volt gauge is reading a little high.....