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Accessories work, It starts with TDR Red and Purple jumped. When running in this mode, it does NOT CHARGE. No alternator output.
Cannot get a reading from fuse 14 terminals looks like -.03 with battery side grounded
Yellow black and Yellow jumped with KEY IN START position, flashed 8.+ volts.
- I pulled the old VIPER Alarm wiring harness. it had not worked in years.
-I took dropped the starter to clean up the contacts and tested it.
- I followed Bill Curlee's lead on Ignition RR.
I am in the same place I was a week ago.
I have a new 850 amp battery and have been using cables to my diesel truck as well.
How did you check to see you had no alternator output ????...with the car running what does your DVOM read when hooked up across the battery ??...now let’s check for a voltage drop on the positive side of the battery...connect red DVOM lead to battery positive and black lead to the B+ stud at alternator...what do you see ??...should be .2 to .3 volts. Now do same thing between battery negative and the case of the alternator...what do you see ??...I think I read less than .1 volt when I had checked mine last year..now check if maxifuse 50 is not blown...now see what your voltage drop is across the ignition switch....positive lead of DVOM on battery positive...black lead to any of the 2 test points on top of fuse 14 while cranking...what do you read ??...should be maybe .1 or .2 !!...if you read 4 volts for instance and your battery is at 12 volts you are dropping 8 volts across the ignition switch !!
The alternator should be pulled and tested, it does not matter that the car starts when you jumper at the TDR, it should be charging. The TDR positive relay coil is powered by 12v that comes from the ignition switch thru the clutch safety switch or the park/neutral switch if auto. The negative side of the TDR relay coil is provided a ground by the BCM if everything is okay with the VATS. You have to determine why the TDR is not being energized, hope this helps.
I really didn't have to test the alt to know it wasn't charging. After the start with the TDR jump, the battery lasted about 5 minutes before it discharged down to 8 on the DIC and died. I peeled back the connection on the back of the alt for + and used the frame for a - 0.00 on the next start.
Given the TDR jump start, would prove my starter connections are correct? It was pretty dark and pretty much had to work by feel
If you have VATS problem the A1 side of TDR relay will not be grounded by the BCM .
If you make a temporary short fra the A1 side of the TDR relay to ground G104 .
If you have a VATS problem your car should start now when you try to start the car .
I'm assuming the C2 side-YEL which goes to the Park Neutral is good, because I haven't touched it . I believe a ground on YEL/Black (BCM Starter Enable Relay Control) is the culprit. I will be over there sometime today to try it.
Note.. The 1998, it's a Starter Enable Control, while later models have a Fuel Enable Control
Originally Posted by oelarse
If you have VATS problem the A1 side of TDR relay will not be grounded by the BCM .
If you make a temporary short fra the A1 side of the TDR relay to ground G104 .
If you have a VATS problem your car should start now when you try to start the car .
To verify if the TDR logic within the BodyControl Module works correctly and ground the A1 side of the TDR relay , you can remove the TDR relay ,
set your multimeter to measure resistanse between A1 socket and G104 on passenger side.
When you move the ignition switch to start position the resistance value shall go from very high ohm value(open circuit) to close to zero ohm .
If this does not happen the BCM is not grounding A1 side of the TDR as it should have done
I simply had to go out to my garage and check this out on my own car . Plenty of sparetime time in these Corona days
First I connected my multimeter to G202 (in passenger side) and the yellow-black term of the TDR relay socket .
Measured 3.3 mega ohm , switch ignition key in start position and resistance went to zero ohm due to my BCM grounded A1 side of relay socket to G104 .
This indicate good ground continuty with G104 (engine room) and G202 (in passenger lower part of A-pillar).
Secondly I connected my multimeter to A2 relay socket (yellow wire) and to G20 .
I measured zero volt at first , but when I set my ignition key to startposition I got 12.2 volt on my multimeter .
This indicated that the 12.2 volt from Maxifuse 50 got through the ignition switch , Minifuse 14 , ParkNeutral and backup ( I have auto trans) switch without any voltagedrop .
Hope this info helps you out in troubleshooting the TDR relay
wow nice pictures. I was looking for voltage my mistake. I am looking at A1 yel/blk for 3.3 MegaOhm turn key to start = 0 looking for 12v on the yel (C2)
last night, it was getting late, and I wasn't getting a voltage reading at all on C2 (yel) to ground. I was using a dash screw for ground 🙄
I pulled the alternator out and it is good. but registering 0.00 when hooked up. I must have a bad connect at starter? I'll return at about 3pm to jack it up and look.
it is in a parking space, a long way from my garage.
No Start BCM TDC TDR BCM Ground
. I believe a ground on YEL/Black (BCM Starter Enable Relay Control) is the culprit. I will be over there sometime today to try it. 
