PRND321 Lights, Oil Level Light, Temp Gauge

[ktmccrary]

This is a new thread as there are only 3 problems left to resolve on this 98 GTP 3800 SC HUD. These issues were last covered in a similar post last posted 12/2.

1. The Oil Level Indicator light comes on whenever the engine is running and the transmission is taken out of PARK. Precisely, the light is OFF in Park, 1, and 2, but is ON in R, N, D, and 3. I have replaced the Oil Level Sensor and thoroughly cleaned the connector at oil pan. PROBLEM PERSISTS.

2. The PRND321 Indicators on the I/P work as follows: In P and in 3 both, the indicator on the panel is "P". In all other gears, RND21, no indicators are lit on the panel.

3. The temperature gauge never moves off min, except when first turned on, at which time the needle moves to max and back to min over a period of about 1 second, then never moves off min while running. Scanner reveals engine does appear to operate at normal temperatures. Found that this is a 3-wire sensor, meaning the scanner and gauge get their signals from the exact same source via different wires. I concluded the output was bad for the gauge from the sensor and replaced the sensor. PROBLEM PERSISTS.

I replaced the instrument cluster to get at least 1 if not all problems resolved to no avail. ALL 3 PROBLEMS PERSIST.

I replaced both battery cables including satellite cables because I found that the battery wasn't anchored and at some point both the + and - parallel and both wires had gotten into the SC idler pulley. The wires were significantly compromised with a lot of green corrosion. Wiring replaced and solid grounding assured, ALL 3 ORIGINAL PROBLEMS PERSIST

Can anyone give me something specific to check to help find and verify the source of these problems? Any help in this matter will be greatly appreciated, as it seems these problems must all originate in the same place, or maybe not. Thanks

[tblake]

This one almost sounds like a faulty ingnition switch/harness to me. I would be suprized if replacing the ignition harness does not cure at least one of the issues. Probably will fix all 3.

There is a write-up in the tips and maintenance forum on how to chang it out. I have never had to do one on my car so I can't help much. The process looks pretty straight forward though.

[ktmccrary]

I was hoping the ignition harness would fix this because I've already had to change one on my 99GP, where it had different but multiple wierd problems that the harness did fix.

Well, this is the 5th major purchase of something that fixed nothing and I am getting distressed. Replacing the ignition harness, the instrument cluster, the oil pressure switch, the temp sensor, and the battery cables, and MY 3 PROBLEMS PERSIST.

Also, the dude that had this before just cut the wire connector off the oem stereo. I still have the stereo but not the connector and will be replacing the stereo anyway. But I cannot reconcile the wiring in my car with any wiring diagram, and in fact have a couple of extra wires I can't account for. I only mention this because it is entirely possible one or more of these wires may not go to the stereo.

I have positively identified BLK/WHT, DK BLU, LT BLU, ORG, BRN, YEL, BRN/WHT, GRY/BLK wires. I am left with a LT GRN, DK GRN, DK GRN, TAN, YEL, DK BLU, DK GRN, BLK, and GRY. The 1st 4 of the 9 left should be front speaker wires but I could get no ohm reading so I suspect both speakers are blown.

So here's what I have:
BLK/WHT GROUND VERIFIED
DK BLU RR + VERIFIED
LT BLU RR - VERIFIED
ORG BAT/MEM VERIFIED
BRN LR + VERIFIED
YEL LR - VERIFIED
BRN/WHT DIMMER VERIFIED
GRY/BLK LIGHTS ON VERIFIED
LT GRN SHOULD BE RF +
DK GRN SHOULD BE RF -
DK GRN SHOULD BE LF -
TAN SHOULD BE LF +
YEL SHOULD BE ACC/PWR ON - NO VOLTAGE PRESENT
DK BLU UNKNOWN
DK GRN UNKNOWN - 12V PRESENT WHEN IGN SW IS ON
GRY UNKNOWN
BLK UNKNOWN - This wire has a 1-pin connector and is
folded and taped to the wire harness in the back, not
with the other wires and also has 12v present with
ign sw on
There are also 3 wires on a separate connector I presume of to the
steering wheel controls. There is a LT GRN, DK GRN, and TAN wire there.

If anyone can help with this it would be great. Maybe one or more of these unknowns are responsible for the other problems. Thanks.

[tblake]

So you have replaced the ignition switch and it still has the same issues? Thats odd. I will pull out my wiring diagrams and see what I can find for those wires.

Doesn't it just frustrate you with what some people do with wiring in their cars? A 5.00 wal-mart plug would have made aftermarket deck installation easier, plus the factory wires could have been left alone.

[olopezm]

Hello,

I guess you must have the radio with amplifier version, try this diagram in case is not the same you have. As far as I've read it seems to be the right one according to the colors you have listed.

Best regards,

Oscar.

[tblake]

Good call Oscar. I never even thought of that. I wonder if any of those grounds or power circuits share the same circuit as the PRNDL indicator, oil level light or temp guage.

[olopezm]

Thanks Tim!

There are no shared grounds however these DO share the power from the box at the right strut in the engine compartment. It is the orange wire and they splice at S202 in the diagram. Do you think this could be the cause?

Best regards,

Oscar.

[tblake]

defenatly could be the cause.

[tblake]

Pretty sweet looking prix in the garage! I wish mine looked that nice.

[olopezm]

Originally Posted by tblake

defenatly could be the cause.

I forgot to upload the instruments cluster diagram, hope it helps

Originally Posted by tblake

Pretty sweet looking prix in the garage! I wish mine looked that nice.

Thanks again!, It's my daily driver and I try to do my best although it still needs some work specially with the paint and some dents. Last thursday the CEL went off after being on for a long time with an evap problem (I replaced everything but the canister). I guess I'll never know what was wrong LOL.

Yours is hot too specially being a GTP; I like the color, I've never seen that one here in Mexico.

Best regards,

Oscar.

[ktmccrary]

I will check those connections at the box tomorrow. This had a factory unit in it with no amp and there is no PINK wire in the harness. I am hung up on this DK GRN Data Link wire. What does it connect to on the radio? What is the black wire with a single pin connector behind the radio folded about 3 times and taped down at the back? If a blue wire is for the SWC's what is the multi-pin connector with only 3 wires in in for with a DK GRN, LT GRN, and TAN wire for?

[Blue Bowtie]

Your scanner should have a display line for the selected gear range. If the scanner reports the correct range for each position, you can assume it's not the fault of the neutral safety/range selector switch or its wiring to the PCM. That may be helpful to know.

[olopezm]

Originally Posted by ktmccrary

I will check those connections at the box tomorrow. This had a factory unit in it with no amp and there is no PINK wire in the harness. I am hung up on this DK GRN Data Link wire. What does it connect to on the radio? What is the black wire with a single pin connector behind the radio folded about 3 times and taped down at the back? If a blue wire is for the SWC's what is the multi-pin connector with only 3 wires in in for with a DK GRN, LT GRN, and TAN wire for?

How many pins does that connector has? That might be part of the instrument cluster!

In the second diagram I uploaded you can see a pink wire (power) for the PRND321 decoder. The multi pin connector you mention could be C2 in that same diagram, which could include the other unknown wires you found hanging loose.

Best regards,

Oscar.

[olopezm]

Now I'm pretty sure that multi pin connector is where are your problems are coming from. I forgot to upload the second part of the instrument cluster (sorry about it) and from it it can be seen the TAN color is the OIL PRESS wire. Definitely the other guy mess the wiring big time!.

I bet once you put the loose wires in the multi-pin connector and plug it in all of your problems will be gone.

Best regards,

Oscar.

[ktmccrary]

I took some pictures, but I need to figure out what size and resolution the site requires, and I think it will help. I have found other issues in this process. The connector with the 3 wires, LT GRN, TAN, and DK GRN, are on a 9-pin connector utilizing the middle 3 pins and it directly fits a seperate connector on the back of oem stereo. And it will not reach the instrument cluster.

There does seem to be a 3rd connector on the cluster for which there is no connector but it is probably a factory test connector, between the 2 functional connectors.

When I looked at the back of the fuse panel in the engine compartment I found 3 double splices. It appears that a small PNK is linked back to a small PNK. A GRN/WHT is linked back to a GRN/WHT, but a small BLK/WHT is linked back to a larger solid BLK wire on the block. I have clear pictures of this and will post shortly, after I figure out what to do.