P1698, 1685 codes on 2001 Export Neon with 41TE Transmission

breezerabbit · Post by **breezerabbit** » Sun Oct 09, 2011 2:15 am

I would really appreciate your good advice concerning a 2001 UK Neon with limp in P1698. Unfortunately export Chrysler Neons received the 4 speed ahead of the domestic Dodge-branded cars and I have comms issues between TCM and PCM. All grounds are 100%, as are all interconnecting loom wires and connections. The o/p speed sensor is AOK. Water / road salt have compromised the gel covering on the TCM, and water seems to enter the unit whether it is driven or not. I have installed a known working, matched PCM and TCM from another 2001. Predictably, the SKIM has intervened, and it has thrown P1685 and disabled the ignition. If anyone could suggest a cost-effective way out of this situation, I really would be grateful. The car is worthless, and yet - I really like it! Cheers everyone. MARK hillmer@tiscali.co.uk

Jenni · Post by **Jenni** » Sun Oct 09, 2011 3:29 am

4 speed > 3 speed!
better handling, better mileage, better everything...

P1698 = bus communication problem

does the PCM come from another Neon WITH automatic?
(I think so cause you wrote TCM + PCM but i wanna be sure)

i found only this:

Check the red/white wire of the TCM for power. It should have battery voltage (+10-12 Volts). If not, test by clipping that wire and supply FUSED battery voltage to the module.

Post by **occasional demons** » Sun Oct 09, 2011 10:45 am

Try using your original PCM with the new TCM. I don't believe they both need to come from the same car. (Neon) The replacement TCM should work fine with your original PCM. You may have to do a "Quick Learn Procedure" to get the replacement TCM set to your 41te. Otherwise, you would need the VIN/SKIM flashed into the replacement PCM to get your car running, or the SKIM module/keys from the donor car.

I would try reinstalling your original PCM first. It is simple, and free.

I have replaced PCM's on older PCM/TCM 41te equipped cars without changing the TCM, and never had an issue. Don't see why it wouldn't work the other way. The only (simplified) communication is the engine and ATX sensor data, so the TCM knows when to shift, and the PCM knows what gear the ATX is in. There isn't any security stuff shared between them.

breezerabbit · Post by **breezerabbit** » Sun Oct 09, 2011 11:50 am

Thanks to 'Jenni' and 'O Demons'. Wise words from both. I have checked that red/white wire, and all places where 12V should be on the TCM / PCM. The two control modules did come from the same 41TE Neon. I did wonder about sticking the old PCM back (with fingers crossed), and with your encouragement, I will do exactly that. I will report back when the replacement is complete. I could probably get the SKIM and the keys from the scrapyard, so will ask about this. It's certainly an exciting life when you own an old Chrysler - and I have got two! Thanks again. MARK

breezerabbit · Post by **breezerabbit** » Tue Oct 11, 2011 2:47 pm

Eureka! The fault was with the TCM. I couldn't use the donor PCM as the SKIM device intervened and killed the ignition circuit. Gladly though, the fault lay with the TCM, and with a donor unit and the original PCM the speed reading came back, and the dear 41TE started to shift up and down on cue. The sense of relief is tangible - thanks again for your encouragement. Cheers mark

Post by **occasional demons** » Tue Oct 11, 2011 3:21 pm

Midnight_Rider · Post by **Midnight_Rider** » Wed Oct 12, 2011 1:26 am

Off-topic but please start an Introduce Yourself! thread and post pics of said export Chryslers. Cheers back at 'ya!

Jenni · Post by **Jenni** » Wed Oct 12, 2011 3:52 am